Look up the skins as they appear in game, and if they don't strike you, play the champion vanilla for a while. If you like the feel and your doing well, keep him. If not, then choose another champ that suits you better. What I have found from playing Yorick is that his lack of a good snare and his focus on dealing higher damage by having more ghouls out makes it difficult to pin your opponents down. You have to trick people into fighting you, because your Q doesn't give enough of a MS boost to keep you on them without ghost or your W. Harass them with E until they try to trade you, then E-Q them and auto attack, moving between attacks to get behind them. When they start running from your damage, W them and repeat the Q-E. Unless they are in the mid levels of HP you usually won't kill them without a summoner spell or team assistance, so when they get out of range don't get greedy and just go back to farming the lane and watch your back for jungle ganks.