Applying skins serverside

I’m trying to make a custom skin for a gamemode we’re working on. I’ve made the skins for the characters we plan on using, but when I upload it to the servers “\materials\models\humans\male\group01” folder (that’s the one I’m working on right now), the skin doesn’t download and no one can see it in game. I suspect that the process behind installing a skin on a server differs from installing it client side only. Does anyone know how to do this?