Just by reading hacker news daily, you will build up ideas and skills (to build skills I recommend going through the more tutorial-based posts on HN). Most people don't even know what HN is, so you're already a step ahead of them.
I'm guessing you're into programming so pick a few languages and learn them in your spare time - http://stackoverflow.com/questions/194812/list-of-freely-ava...
For idea development, keep reading posts on HN, TechCrunch, GigaOM, VentureBeat, etc. Spend a few minutes daily writing down words / trends you notice for startup ideas / startups that are doing well and others that are doing bad. As you do this more and more, you'll start to notice really great trends, and you can iterate on them. Also for ideas, go through your day and write down every pain point on a sheet of paper (the writing part is important, typing it in isn't as useful!). As you build up both pain points and trends, you'll get the hang of mixing / mashing ideas!