Help makeing a macro please?

Ive been trying to make a macro either dll or exe it doesent matter. I had one that someone made and explained but it didn't work v.v Id to make it so that it automatically starts and kills itself in ava (to make mini farmer auto) or if you don't want to, id like to make a macro that makes your gun shoot slower(idk if you know what I mean ill try to explain more if you don't). Thank you