>>298812231
Start with importing multiple avatars with good optimization.
After that try to frankenstein something, take a head and put it on the body of another avatar. Its harder than you think and can fuck up some of the data but its a learning experience. /vrg/ can always help fix your fuck ups.
Then try making your own mesh and put it on your avatar. I suggest start by making custom buttons and attach it to the chest and stuff like that. It teaches basic mesh design as well as UV mapping.