Imagine the game you really want to make, then set it to be your 3rd (or 4th, or 5th...) game. This way you do some really easy games before it to get in the flow, publish then, learn with then, and you will have the XP to go to your 'real' game.
This is what I've set to myself after getting some advice from experienced people. At first I was trying to make a game with mechanics that I had no idea how to make, and not even the internet. So I killed this project and started with a small one. Now I am finishing the second one, and now I know how to make that mechanics, it works.
Art imitates life, get better before go to the boss