How do you know when your partner is ready to be penetrated?
Of course, your first answer to this question should be when you've asked her if she is open to it and she has responded with an enthusiastic, resounding "yes."
Beyond verbal consent though are some unique bodily signs that you should try to be attuned to.
Engorgement. As we get aroused, blood flows to our genitals. Penises get erect and vulvas get engorged. The colour of the skin of the labia may even change, darkening and reddening with the increased blood flow.
Lubrication. Whether with her own natural fluids or with some applied water-based lube. Lack of wetness can be uncomfortable for everyone involved.
Hip placement. Often tied in with the verbal and physical desire to be penetrated, your partner may move and tilt her hips toward you, like a gesture. This may also involved an arching of her back.
Sound. Aside from the continued checking in and verbalizing of consent, listen for moans, sighs and other vocalizations indicating escalating arousal and desire.
Energy. Tune in with what you're feeling in your own body and then see if you can pick up on what your partner might be feeling in her body. Notice any tension or something else that may make you feel that she isn't ready.
Lastly, when you've really slowed down, payed attention to her, honoured your own sensations, built arousal and pleasure together, and responsed to her cues, both verbal and otherwise, hold the head of your cock at the entrance to her Yoni. Again, check in. Notice what you both feel.
You may even notice that, if she is ready, her vulva will draw your cock in, almost inviting and welcoming it into her vagina, slowly, subtly, gradually. The Yoni is the sacred receptacle, the receptive pole, it can pull you in just as much as you can penetrate.
Here in this moment, in this point of almost piercing the veil, about to enter the temple, ask again, "Are you ready?"