That would depend on what you already did, of course. Looking at the linked files, I'd say you need to: 1) Make a 'models' folder anywhere; 2) Make a 'zygerrian' folder inside 'models'; 3) Put the downloaded files into 'models' -> 'zygerrian'; 4) Add 'models' to a .zip archive, name it any way you wish (i'd name it 'zygerrian' too); 5) Change 'zygerrian.zip' file extension to 'zygerrian.pk3' file extension (may need to dig around your computer's folder options to make file extensions visible and editable); 6) Put the new 'zygerrian.pk3' into your game's 'base' folder, if you didn't save it there innitially; 7) Run JAMP and find the skin in the skin options. Note: You might need to also make 'icon_default.jpg', 'icon_gun.jpg', and 'icon_2.jpg' inside the 'zygerrian' folder, to be able to find the skin in the list, some skins don't show at all, if you don't assign an icon to them. I'm not sure if 'model_gun' and 'model_2' are character skins though, I didn't download the files.