How to Create Models/Skins on a Mac ?

Helloo, I have a very mac related question that I havent seen before . It is very simple too . How can I make skins/models on a mac ? What program(s) do I need ? I do not have PhotoShop nor do I want it at all .
I also cannot open vtf. Files, to edit skins/models if I wanted to .

; Lobster<3

Another note ; Just for a Laugh Sticker ;
When you slip and land on the road, Its yo’ own AssPhalt (Ass fault ) ;D

Check this thread for information. It can be done on a Macintosh just like on a Microsoft DOS/Windows PC