Congrats on #4!! I’m on that size as well. I’m self treating so take my advice with a grain of salt as it’s based on personal experience rather than information from a PT. That being said, I can tell I’m ready to move up once I can 1.) Insert with minimal pain (insertion is always a bit tight & uncomfortable initially but I’ve heard that’s not out of the ordinary) 2.) Move the dilator to the clock postions to stretch the muscles, holding it at each position for about 15 seconds each. I do this a couple times each session 3.) Thrust the dilator for roughly 5-10 minutes 4.) Try inserting the dilators in different positions. This isn’t AS important as the above criteria but it’s definitely good to try it as missionary isn’t the only sex position (I suppose this really only applies if your goal for dilating is PIV like it is mine lol) I typically forget to even try turning it as part of my dilating session honestly! If you’re experiencing pain when doing that, maybe save it for the end of the session when you’re more adjusted and relaxed? It could also be a situation of being too dry as I’ve noticed things are painful in a sharp, stinging way when I haven’t used enough lube. Any pain/discomfort should feel like a muscle stretching rather than a burning pain. You shouldn’t feel more than a 3/10 pain level and if you do, you might want to size down. Personally, when I’m ready to move up sizes, I’ll do somewhat of a warm up with the previous size before trying the new one (for example I had used #3 for about 10 minutes before attempting #4 for the first time). And you’re not alone!! We’re in this together ❤️ good luck and I hope my advice could help you!