I would second ambershee in putting your ideas on paper. You should look at writing your Game Design Document. There are some good templates to get you started online if you search for it. However, before tackling all of the paper work you should work on writing out the general concepts of the game on paper before diving into the detail. One good and fun way to do that is to actually imagine what the game case would look like, and draw/write it out. Typically on the back of a game case you have a few pictures highlighting visuals of the game, and 5 to 6 points that highlight the unique aspects of the gameplay. It certainly isn’t a required step, but it’s actually a fun exercise that helps you work out the premise of the game before diving into all the detail.