Some background info: I'm 23, np, med-low cervix, 5'6" but very slim (all of which led me to believe I should need a small cup). I found out about menstrual cups while researching before getting my IUD. I decided to get one in anticipation of heavier flow and WOW was I right! So much heavier than I ever expected!
Not so successful beginnings: I had been using a small green donna, which was fine on my spottier days, but I leaked alot on my heavy days and I found it uncomfortable firm at night and upon removal. After SO MUCH research (shout-out to the Q&A section!) and a fateful mc_sales transaction, I came to possess a large soft MeLuna. I was looking for a medium but I was offered a great deal on a gently used large and decided to go for it.. so glad I did! Apparently, I'm wider inside than I thought! I think my green donna was leaking because it was too narrow.
At first: I had a helluva time getting my MeLuna to open. C-fold, punch-down, 7-fold and origami all failed to open (even after employing the trusty wall-push move). It just would NOT open.
But I was determined: I finally tried the half diamond and hallelujah! I still need to do the wall push thing and some other twisty prodding and maneuvering, but its open! and no leaks! and soo comfortable I seriously can't feel it!
I am so thrilled right now :) Yay for MeLuna! Yay for the half-diamond fold! yay for you wonderful soul on mc_sales and yay for this community for sharing your experiences and all your wonderful information!
1. Don't assume you need a small cup because you're smaller, or a large cup because you're larger.
2. Your goldilocks is out there!
3. Experiment with folds!