(09-29-2015, 03:54 PM)plignis Wrote: hey just wandering, i am starting to learn how to programme and i wanted to know if anybody could give me some tips to try to make a gmod addon, like a HUD or a tab menu
You need to learn the LUA scripting language, Gmod and its addon's are written in LUA.
Unfortunately i could find any completely newbie friendly online lessons or courses, but there is a good introduction to LUA here.
Once you are able to understand LUA, or have a good basic understanding, you should be able to follow the tutorials listed on the Gmod wiki
Good luck! Hope it helps.