Muscle-ups are pretty difficult, but they're definitely fun to do. If there's an empty pull-up bar in your gym that you can play on, do some practice! They're just one of those movements that really test your athletic ability.
Don't forget to time your rest as I have it programmed. Because you're not in the gym every day, you need to get your heart rate up when you're training. The best way to do that is take less rest and lift hard!