No matter what you choose, build stuff and be around smart people.
Good startups usually take 10 years.
At the beginning, you should only hire when you have a desperate need to.
Be suspicious of any work that is not building product or getting customers.
You have to save the vision speeches for when the company is winning. When you're not winning, you just have to get momentum back.
One of the biggest advantages that start ups have is execution speed and you have to have this relentless operating rhythm.