Concentration, much like everything in the mind, is a skill you have to develop. If you keep at it you will see results rather quickly.
There are so many exercises out there, read some books, experiment, see what works for you. The important thing is to TRY. You will get results and be amazed by what you brain can do. My advice is to start as soon as possible. This won't happen in a day, the mind is a muscle, you have to train it. The only difference is that you don't "feel the burn". Early on every exercise seems empty and pointless but then one day you'll be like "HEY! I remember that! Where did that come from?". Trust me you won't have to wait long.
So get goin
Here are a few methods I use:
- Make a special study space. For example I can't do anything serious on my bed because it makes me sleepy. Nor can I concentrate around my computer because I have a compulsion to check out the forums/e-mail and jazz like that. I actually have a "thinking" chair in my living room, a relaxation corner and the kitchen table is my studdy area.
- Create a "study" mood for yourself. Think back to a moment when you were really intrested and excited about something, get in a focused state of mind. Then think of a song, an image, a texture or make a unique gesture. Repeat this several times, this anchors whatever it is you thought or did to that mood. Then everytime you are about to study, get yourself in that mood and do your anchor. Eventually, doing the anchor should put you in that state of mind without having to concentrate on getting there.
- Learn to stop those interupting thoughts. Anytime some random thought pops into my head fold it up and toss it in my uper left corner, which is an earea where things to do later go. This works for me because most thoughts are intresting and my mind starts acting like a child. "But I wan't to think about this NOW!" Telling it that it's important but this isn't the time sort of tricks it into getting back on track. This is yet another little trick I thought of by myself.
OK, cheers