Earlier I use to write css style for each class myself, then I started using zurb foundation for css and then I saw twitter bootstrap. But a common problem I face is that I am not able to do following things properly:
1. Make proper layout of site: I am not able to see things without coding css. I mean I use photoshop, any software like that to help me making a proper layout of site and code that. Also, an option to extract each element of layout designed to be extracted as images so that I can use it.
Here is a website which will
Here is a website which will guide you step by step for creating you own personal lay-out.
You might learn something out of it.
It is hard to tell how to do this in a forum as it will take ages to teach you a certain way of creation.
But by reading something like this or similar, I think, you can learn faster.