Number One. Don't start a business if you can't explain what pain it solves, for whom, and why your product will eliminate this pain, and how the customer will pay to solve this pain. The other day I went to a presentation of six high tech startups and not one of them had a clear idea for what pain they were proposing to solve. I saw a startup that was building a way to set a time to meet your friends for coffee, a startup that wanted you to install a plug-in in your browser to track your every movement online in exchange for being able to delete things from that history, and a startup that wanted you to be able to leave text messages for your friend that were tied to a particular location (so if they ever walked past the same bar they could get a message you had left for them there). What they all had in common was that none of them solved a problem, and all of them were as doomed as a long-tailed cat in a room full of rocking chairs.

Number Two. Don't start a business by yourself. I know, there are lots of successful one-person startups, but there are even more failed one-person startups. If you can't even convince one friend that your idea has merit, um, maybe it doesn't? Besides, it's lonely and depressing and you won't have anyone to bounce ideas off of. And when the going gets tough, which it will, as a one-person operation, you'll just fold up shop. With two people, you'll feel an obligation to your partner to push on through. P.S., cats do not count.

Of course following this advice doesn't guarantee success, but not following it makes it extremely difficult to succeed.