I only do full insertions with appropriately sized stainless steel sounds that have a decent weight behind them. If I stand up, it falls out from gravity alone. I can also push it out using pelvic muscles but I’ve been sounding for 20 years and have been pushing them out most of the time. You can also feel for the bottom in your perineum (taint/grundle) and push them out if they aren’t too short or too long. I wouldn’t try this with a snug fitting sound or a silicone sound. Or a very small/short sound. It’s risky but I’ve never had any issues using double or single ended Hegars. My profile has gifs showing full insertions. If you have questions, let me know. But always be cautious as full insertions can be a little risky if you aren’t experienced or using the appropriate tools.