How do i make my mods into .lmlm format?

I've been off for a very long time and now I'm back to stay! :) But i never really understood how to put my mods into that format. So if you guys don't mind please explain to me how to do this so i can get back to modding. :)

Also, i hope i put this on the board, please correct me if not.

I'll check it out, thank you!