You may try out by video, but there is a pretty substantial cost for that. (We much prefer people try out in person, if possible.)
You can see that, and all of our costs online in our tryout/evaluation packet.
Making the floor on Wildcats is a challenge for all but ultra-elite athletes. As another person had suggested, I would watch videos and use that for comparison. There really aren't set requirements, but you generally either need to be one of the best tumblers in the country, an elite coed stunter, or both. On the plus side, it is a phenomenal experience for those athletes.
(Similar things could be said for our other teams, but he asked about Wildcats.)