Both Volen and Stepanovo are mostly man-made hills, so there's no possibility for long runs or off-piste snowboarding. The only thing you can do is to ride across the through the slopes, working on your technique, and trying out your new equipment.
Freestyle
There's a snowboard zone in Volen park, but it's kind of abandoned – just a few bumps. On busy days snowboarders usually gather with shovels and make hits for themselves on one of the slopes. You can also choose the areas between the runs to practice your skills, which is what most snowboarders end up doing there anyway.
Pistes
Very short runs provide no possibility for carving in this park. The only possibility could be in Stepanovo, where there's a 1km long run, but it’s still too slow.
Beginners
If you are just starting to snowboard, Volen and Stepanovo might be a good place, as there is a good snowboard school and snowboard equipment hire (quite pricey, though), the instructors hold the Russian Ski & Snowboard Federation certificates and were trained by the French. Most of the slopes are easy and on a weekday they are quite deserted, so you will feel more confident learning.