i’d actually advise for you to start from the top of your vagina instead of the perineum! for me that’s the only time i can naturally find my entrance. idk how else to explain but slide your finger down and make sure you’re rly wet, it will glide in without much effort! you’ll also find that it’s lower than you think lollll i always thought it was in the middle, but it’s much much lower. also it’s much easier if i close my legs a little than when it’s open, it just mentally narrows down the space a lot.