When you visit the www.acsm.org, locate the link where you can take one of their online webinars that will assist you in preparing for most of the ACSM exams.
The only exam that there is no webinar for is the ACSM RCEP. It’s assumed that you have the education and experience to take that exam.
However for the vast majority of their exams, you can take a webinar in addition to purchase their printed resources in order to prepare for the vast majority of their exams.
I hope this is helpful to you.