Here’s a simple variation on a traditional theme of cunnilingus that should be easy enough for both of you.

Instead of going down on her with her on her back and your head between her legs, try flipping her on to her front with her legs over your shoulders. You can then lick her out from behind, which will stimulate different parts of her vagina. You will be able to get your tongue deeper inside her, which means you can stimulate the G-spot that is difficult to reach with conventional cunnilingus.