Chastity device discussions and reviews discussion

I just picked up one of these with the 50mm ball (wish I had gone smaller). Any advice on how to relax my anus enough for it? Poppers help? Also, regarding the urethral plug: it seems to stop around halfway. I don’t want to push too hard; I can only manage about half its length before hitting a resistance point, and getting it all the way in requires some slight force. Is that safe?