sucessfull advices

he has many traits that make him what he is and that is the reason why he can run three successful companies and take the path that many dread. some that i think helps him achieve this feat are:
  1. he loves his job and his companies. he truly believes in making a big and positive impact for mankind. so when you love your job so much you don't feel that you are working.
  2. he pledged his everything in spaceX. it was on the verge of shutdown but he never gave up. it takes a lot of self belief and confidence to be that bold and continue working towards your vision when everyone else is losing hope.
  3. he just works a lot. he works towards his vision every waking hour. in his own words he speaks about founders working 80 to 100 hours a week. that just means you use more of your time on what you really want to do. although it is not everyone's cup of tea to prevent oneself from getting burnt out.
  4. he is a voracious reader with a photographic memory. he literally has self taught a lot of the varied skills that is required to run three very different companies.

watch the below clip. that may give you more clarity.

Motivation is key

Motivation…
He didn’t learn all three to get a desk job. Well, OK, one could make the case that PayPal was more a “paying gig” than the rest…
But SpaceX has been his passion from the get-go. He sat down with borrowed rocket science books, and since he has a science background, he plowed through them, learned everything he could, then went seeking experts to help him with the rest. He then founded the company because it’s WHAT HE WAS PASSIONATE ABOUT, and what he wanted to do more than anything.
Same with Tesla; the idea of a mass-market electric car with all of the high technology that could be brought to bear - as opposed to what the Auto Industry was doing at the time Tesla was founded “let’s just throw some batteries in a car we already make, and it’ll be close enough…”, was revolutionary. And it was what he wanted to do…
He’s driven to do these things because he drives HIMSELF to do them… not because someone is going to give him a paycheck for them.
That’s awfully hard to replicate unless you already have the drive inside you…
Not saying impossible… but I”m not sure I’d work 18 hour days for years on end, for a couple companies that haven’t really made any money yet!
FYI; I’ve got a small investment in Tesla… and if SpaceX ever sells stock, I’ll buy some of that too… I believe in both companies.

Elon Musk traits that made him succesful

Elon Musk has been working on a lot of ideas simultaneously, but an enormous amount of actual work is done by people working under him. That amounts to thousands of people in various companies. Elon Musk has several traits including but not limited to:
  1. Working super hard work for a very long time.
  2. Intelligence.
  3. Thinking from first principles.
  4. Accelerated training about everything.
  5. Inspiring great people working under him.
  6. His capability to ‘start’.
  7. He does not conceive failure.

  • Multi tasking is not easy for most people, and he certainly is not a normal person. He has some insane work ethics that almost no one can match. He must be constantly thinking only about work, and great ideas all day long, week after week, year after year since last ~ 15 years or more.
  • Those work ethics inspire others around him to do more. He has constantly claimed to be working between 85–90 and sometimes even 100 hours per week and that is certainly not easy to do at all. This trait while possible for many people is very hard to sustain for a very long time. Most people who work that hard eventually give up after a few months to years. Elon Musk has been sustaining it for some time.
  • Most people who have known him, or have worked with him have called him to be super smart. It all comes from first principles based thinking he applies on just about everything. The whole thinking process goes with a semantic tree where he understands the main parts of the tree first, and then the details narrowed down all the way to branches and leaves.
  • He has been reading a lot of books, and they carry some serious amount of knowledge. An average person reads only a book per month. He reads a book in a day, and he has been reading a lot since he was young. Comparatively, he might have read at least 50–100 times more than an average person and knowledge compounds like anything.
  • Great multi-tasking people become so amazing that by the time they are thinking they are typing their emails, they have made their best decisions, and they can do it at a speed several times higher than most people in the world. I have personally seen people like that who are able to think, write, convince, construct ideas on the fly, and eliminate non-value adding things on the fly way faster than a group of people put together.
  • How do they achieve this? They practice one skill at a time, and take to a new height and become ten times better than others. Then they pick up two skills at a time, and try to get better than others.
    • Take this for an example:
      • If you are a better thinker than 90% of the people.
      • You are a better writer than 90% of the people.
      • You can type faster than 90% of the people.
      • Combined ~ You can think, write, type faster than 99.9 percent of the people if all those were independent sets. (Although they are usually not independent sets, but you get the idea).
    • The point is that more skills you multiply, the more and more unique you are as a person, and he is certainly a far more unique person than many others.
  • Talking to a lot of people will usually give someone a lot of perspectives, ideas and inspiration. Elon is surrounded by a lot of really amazing people from all over the world.

I have written quite a few posts about Elon Musk. Check out some of them which are more specific about several aspects that people have asked on Quora.
Check out some of my other answers:

How to manage a company

He obviously needs to delegate, and delegate damn well. But he knows he’s not going to get an Elon to delegate to, so he’s got to be involved, and as he only has a percentage of time on each business he needs to understand enough to make pivotal decisions.
Many of Elon’s reportees would know more about their area of expertise than him, but they’re not him - he’s got that track record and his own money on the line.
Elon’s multiple ventures benefit his companies big time through cross learning. Being deeply involved in multiple companies means he is continuously fuelling cross learnings between ventures at the highest level. I feel this almost on a daily basis with the ventures I have co-founded.
But there are other benefits. He’s undoubtedly more connected by running several ventures. So when it comes to fund-raising, for example, he might have just completed a funding round for Tesla, and then, 3 months later, he calls up the same investment bankers for SpaceX who will be dealing with investors already comfortable with Elon. And his own brand, which comes about from having several ventures, brings a lot to the table.
Elon has not rewritten any rules by running several ventures simultaneously. In fact what he’s doing is tried and tested. Google is no longer just a search company - Android, GV, Google Capital, Google DeepMind, Google X and a whole host of other diametrically tangential businesses all have Sergey and Larry ultimately in charge. Go to Korea and you’ll see that Samsung and other chaebols have been doing the same things for donkey years. And Richard Branson has done this with Virgin Group.
It works.

Companies

SolarCity is already merged with Tesla. 
Tesla doesn’t make just cars, and it’s a more complex company than you can imagine.
SpaceX makes rockets and other things.
Hyperloop One doesn’t have Musk on board. They “stole the idea!!!1111!!!”, but he is not part of the team. -> Hyperloop One - Wikipedia
But instead of Hyperloop he has founded The Boring Company -> The Boring Company - Wikipedia
“an infrastructure and tunneling company founded by Elon Musk”
OpenAI is a research company “associated with” Elon Musk. What is his role inside the company?
Also, the co-chair is Sam Altman of YC. He co-founded with another great entrepreneur.
Neuralink was founded by Musk in ’16 and publicly reported in March ‘17. The product is said to ship in 4 years.
He could make a conglomerate like Alphabet or Amazon which deal with a lot of different businesses. These two companies don’t get enough credit by fanboys (though the stocks are worth >4x than what all the companies owned by Musk could be and Bezos is the second richest person in the world). He keeps things separated because he always bets big -> Elon Musk, of PayPal and Tesla Fame, Is Broke (2010).
So, can you imagine if Tesla ramped up too much debt, produced so many cars at a loss, competitors catched up in 4–5 years, and then a scandal with the proportion of the Volkswagen’s one hit the company?
He’d put in serious danger the project of humans on Mars.
What does it take for a normal person to multi-task at this range?
a) Elon Musk is not normal. It’s like asking “how do I become MVP of the NBA finals if I’m 5′10 and I’m not a basketball player?”. It doesn’t happen. Period.
b) He is not multi-tasking here and there. He is focused on one thing and one thing only -> Succeed. He can’t say “oh, I allocated 3 hours at SpaceX this morning, let me take the corporate jet and see if I can get to Tesla’s in Palo Alto and do 3–4hours of work there”. No, he is exactly and always where he needs to be. Where he makes the biggest difference. Mark Zuckerberg said something like “If I’m not doing the most important task of the day, I’m wasting my time”.
The best advice I can give to you OP(!) is to cut all the carps.
Good is the enemy of great.
You need to focus on the things that have the biggest impact, you need to skim things that are just good, and go where the hard things are.
I get very disappointed when I see a long answer with a lot of upvotes which is not relevant to me -> I lost minutes of my precious time, and for what? To get insipration? to get motivation? JUST DO IT. Don’t read Quora all day long.
Do you think Musk is going to read my answer? lol.
Do you think he cares what they tells to him on Twitter? Well, maybe…
Given that it’s a PR move, very successfull (and IMHO there’s a lot to learn from him and Marc Andreessen in this regard, if you are a CEO).
He knows how important is the perception of his ventures for the good of his companies.
Good PR -> high stock price -> higher ability to raise capital to fuel not-yet-profitable companies.
Could the SVP of engineering at Tesla have the impact he has at doing this task on Twitter? No.
But I’m sure that the SVP of engineering is (one of) the best fits for his role. Who put him there? Probably Musk.
One last point:
As User-11195922798142823543 says he is not alone in this.
 I think it’s naive (don’t get offended) to think that he is a one-man-army.
Every great entrepeneur knows that you need to attract the best talent and drive higher the curve of skill set in your company -> hire better than you.
You must delegate and not micromanage, especially at the scale at which Musk operates.
If I were an employee I’d find disrespectful that somebody thought that the CEO, and the CEO only, did all the work.
Bonus:
Go, check this link, out yesterday, great reading: 
Neuralink and the Brain's Magical Future - Wait But Why