I got a better idea - figure out the goal of your startup before you do anything.
Do you want the freedom of owning/running your own business?
Do you want to make lots of money?
Do you want to experiment with new technology?
Do you want the satisfaction of building something from start to finish, making all the decision?
I think that is my biggest regret in building my startup - I did not have a clearly defined outcome. Sure I want to make tons of money, add new skills, learn ruby on rails, build something from scratch, add something to my resume, learn how to start a business. But I think more than anything I wanted to build something and see it to the end.
I did make some compromises along the way but building something and showing it off as my own has been the biggest rewards.
If money was the most important thing I should have done things a lot different, i.e. talk to customers early. Do you want to build something you believe in even if people tell you it's not a good idea (I did) or do you want to fill a need in the marketplace? Figure out what your highest priority BEFORE you start building your startup. That is the best advice I can give you, considering that I've been flailing away at my idea for 2.5 years, on and off.