Last week, I put up something about world building as my post. I mentioned a spread sheet of ideas. In a comment I received, the question was posed, "What do you mean by a spreadsheet of ideas though? I can't quite see that in my head. Would it be possible for you to maybe put up an image for example?"
So I've decided to include a couple of my spreadsheets to show you what I do. The first spreadsheet is a character list. I list each character in my books, three characteristics, basic hair/eyes information, and any other notable physical characteristics.
The other spreadsheet I'm going to show you is the one I used to sort out my races. It's very much like the character one, except that it has different information required on it.
I also leave myself notes on things, whether it's a character who decided to pay me a visit or a dream that won't go away.
However you keep track of your world building and story ideas is fine if it works for you. This is just a small example of what I do for my projects.