Dota 2 Mod Manager

Dota 2 hero item mods

One slot at a time, for when a whole set is more than you wanted to change.

The D2PFX catalog has 130 mods in this category. Each changes what you see on your own screen; everyone else sees their own game.

Installing any of these

Open Dota 2 Mod Manager, find the hero, press Install. The app puts the file in a free pak slot in the folder your game mounts, tells you when two mods carry the same file, and puts everything back after a Dota patch. The full guide, or the manual route if you would rather do it yourself.