Why DeviantArt? Simply because their built-in commission system makes the process smooth and tidy enough for me to actually make occasional commissions possible.
After reading the details on the page linked above, all you have to do is submit your request by clicking the "order commission" button (requires a DeviantArt account) and make the purchase. If I accept the request, the money is then held for me by DeviantArt while I make the art for you! I wish more platforms handled commissions this way...
Anyway, I've had a lot of requests for avatar commissions, but sadly had to turn so many of them down due to lack of time, so I've tried to come up with a solution that I'll be able to work with during my small windows of opportunity.
Lots of love to you all, and shout-outs to my three lovely example chibis: @zoesfancycakes , @BaconStudio , and @ColesyGaming !