You should start making your great game idea right now. While you are reading this other people are producing and releasing. Your great game idea is nothing if you do not release it. It is worthless if it is setting on your hard drive.
So why not start now? Most people don't know where to begin. Well I say start with A non programming engine such as scirra's construct 2. This engine is so easy to use and you can start making your game. If you do not have a PC you can use game salad for mac.
Start making as many games as you possibly can. The more games you make the better you will be at making games. You can release your awesome game idea and you develop a new skill.
Remember today is a great day to start. Not tomorrow, today.