Question about being a drill sergeant in the Reserves

I'm debating in my head whether or not I want to go the drill sergeant route and I heard they interview you before you go to the unit. Is this something you can pass or fail? If so, how do you pass the interview? Also, what will they think or say if you show up to the unit on the first day and don't have the top 3 memorized already? I'm bad at memorization. The Drill Sergeant Creed is easy for me though.