As somebody that teaches this course, I would recommend you go the other way. Part of the course is how to carry and work with a deco bottle. Practicing with it before hand isn't going to help if you are practicing it incorrectly.
Practice diving in the rig you will use. Practice the various kicks, work on motionless stability. These are all pre requisites to that course.
Showing up to an advanced level course without the prerequisite skills will turn your ANDP course into an intro to tec course. Being able to carry stages and deco cylinders isn't something you need to demonstrate on the first day.