You could start choosing a easy programming language (dont hesitate much about this) and looking for some good tutorials.
Personally I recommend you read the following article: http://www.gamefromscratch.com/post/2011/08/04/I-want-to-be-a-game-developer.aspx. Contains very useful links to start on the programming language that you want.
I hope I have been helpful. Greetings!