[avivelkayam]

if you have file to player you can set a Key "Skin" and to set him -1 (this is when he is not saved the skin)
when he save the skin command or somethink

you can set the key "Skin" to the skin of the player
and in OnPlayerSpawn you check if the Key "Skin" != -1 than you set the skin of what the value in the key "Skin"