Big Dick

So my boyfriend’s dick is huge . It’s so big to the point I can’t even do majority of the sex positions I like . I don’t ride him , cause when I tell you I feel all the pressure . Like I really be feeling like he’s rearranging my guts at time . Then he’s this muscular guy with a high high sex drive . So I would just lay there and take it cause I’m scared he’ll hurt me . He’s always told me that he doesn’t want to hurt me or that he’ll never hurt and so far he hasn’t , I just wanna know like how am I suppose to ride him without feeling so much pressure , don’t get me wrong the sex is amazing but I wanna do & try new things . I mean when I was with my ex I could do those things cause his dick wasn’t all that big . Help me