The way to get better at anything is to obviously practice. However even before this, you have to be not just interested in the game but "very" interested. I can't stress this enough because becoming a better chess player requires this. The game chess is not just a game to be played, but studied. Studied right from the beginning postions.
Most games of chess are played using the same techniques. Positioning and being observant. Once you get a hang of those two things, you would be surprised how much you can improve.
Many people that know how to play chess but can't grasp how to win can be explained. As I said before, you have to be interested in the game! So, let's assume you are very "interested" and want to start winning.
The first thing is to forget about how many moves you can think ahead. That just comes to you naturally. Nobody can teach you that. The main idea is to just be observant. Learn opening moves that are only two or three moves. That's all ! The rest of the game is just being...(what's that word)..? OBSERVANT ! As time goes on you will automatically remember and it's all straight forward from there. I'm not any top player by far but I do know what helped me out. It was the openings or the first two or three maybe four moves. From that point it's all about looking for your opponets mistakes. You know..the "oops, didn't see that" kind of thing. That's how you win. Looking for mistakes! It's not all based on how far ahead you can plan. You can win many game just with openings and positioning your pieces in wierd spots on the board. Just look for oppertunities or mistakes. Trust me, we all make them. You just have to find them, that's all.
Buy yourself a sizable chess set. Maybe one of those roll-up kind. They are cheap and the same size as the ones used in tournaments. Play an opening all by yourself. Pretend you are playing someone. Make his moves. Everytime you do this,,observe the board. Stare at it and study it. What can you do, what can he do? Go into the game maybe three or four moves, that's all. Don't play an entire game. You'll never remember all that. Right now you are studying the game, not playing it.