Sex positions

I need some help with new sex positions... currently we only do missionary or cowgirl. My boyfriend is on the bigger side and I’m quite small. He loves cowgirl and I do too but I want to do others as it’s getting kind of boring doing the same every time.We rarely do missionary because I usually feel like I’m being crushed😕. What other positions can we try? We’ve tried a few but they just don’t really work