i make simple games. how to put/configure them on emulationStation/RetroArch?

You can create your own .sh scripts (Emulationstation recognizes these automatically) to launch whatever you want, so assuming your games run on a Pi you can just create a shell script for it and place that in your ports folder (or even create a whole new seperate category for them).
Just look at a few of the existing .sh files to see how they are set up.

Start a thread on the RetroPie forum with links to your sources (preferably on github) and I wouldn't mind coming up with a module template to try out some of your games (that way you can compile them and have them configured to launch from ES automatically)

What about porting your games directly to libretro? They would become playable on every platform supported by retroarch.