hawkeyeuk

Hi there I apologise if I am posting this in the wrong place or even if the question has been answered but I am just trying to sort out a problem with my 9 year old boys game. He has Mincraft 1.7.5 and he wants to get the Pixelmon mod to work and I am at a loss of how to help him. I believe it has something to do with Forge but I just cant see how to install it could some one be so kind as to give me a step by step on how I can fix this. Many Thanks Ian