Unless all of your clients are everyone who attends your gym, you're going to struggle during the quieter months when the kids are off school and it's too cold for people to venture outside. If you're new at a club, you're going to find it difficult to build up a clientele at first until you're better established and people will want to invest in you. This means that you need to spend the majority of your time on the gym floor, giving people pointers, leading fun and enjoyable classes and owning your own work outs for everyone to see until you get people wanting to work with you. So make sure you know how to budget for those quieter months when there aren't a lot of people around to invest.