[Jstylezzz]

Save the skin into a variable, and load it each time the player spawns.

pawn Код:

new pSkin[MAX_PLAYERS];

public ChangeSkin(playerid,skin)//just an example, add the code where you have your changing things
{
pSkin[playerid] = skin;
SetPlayerSkin(playerid,skin);
}

public OnPlayerSpawn(playerid)
{
SetPlayerSkin(playerid,pSkin[playerid]);
}

I highly recommend you use enums, if you don't know what these are, search. I've seen some tutorials covering this, so check those out.