I was really nervous, for some reason, but got out my Diva Cup and began the process. I trimmed off about 1/2 of the stem and sat there for like 30 minutes folding and refolding trying to insert it. I had a hard time because as soon as it would be a TINY bit inside, it would pop open. So finally I got it to work, and I walked around with it for about an hour. It was seriously pinching me, so I decided to check if I really got a good seal and take it out and trim the rest of the stem off. I wasn't really worried about not being able to take it out, because during my dry runs I didn't even use the stem to get it out. So I pulled it out and noticed nothing on the outside of the cup and took that to mean success. Then I trimmed the rest of the stem off and put it back in (after washing it, of course!). This time it only took like 5 minutes max.
I have to go to church and stuff today, so I'm wearing a pad just in case, but I'm pretty sure I won't need it. I'm so excited! I hope it gets a bit easier after a few days, but it's nice knowing I won't have to take it out until tonight. :)
So... I'm finally an official cup user! :)