You can start with the searching of some good books on home bars, at your nearest book store. You must go for a book with a simple set of instructions to follow, so that you can complete the job of building a home bar, without requiring any help from an additional source.
Once you have decided the design of the bar you want at your home, the next step is to purchase all the required materials needed to build it. As you are doing this for the first time, it is advisable to go entirely according to the book instead of making judgments on your own.
Do not get frustrated by minor obstacles and mistakes as you are not a professional bar builder and hence must recognize your limitations. Make a point to learn from your mistakes, and gradually you will feel that you are getting better at the job of building your bar.
So finally when it gets completed, go out and shop for your favorites to enjoy in this small heaven build with your own hands.