“Having your partner lie on her side is a great way to put her in a comfortable position while still giving you access to play with your partner’s boobs, slap the side of her thigh, or caress her body. This is also an easy position for her to play with her own clit with toys or a hand. With her hips turned to the side, she gets different kinds of stimulation than in other positions. Have her split her legs so her bottom leg is straight and her top leg is bent at the knee towards her chest.
When you enter your partner from this position, press the head of your cock towards the bottom of her vagina, which in this position is to one side. Tilt her body towards her back or more towards her chest until you both find the angle that feels best. Like in missionary, you can hold her top hip steady as you thrust, or you can bend over and place your hands on the bed at either side of her waist.
Adjust your own position to find the most comfortable angle. You can stay on all fours with your torso parallel to hers, or you can move both hands to one side, so your torso is positioned diagonally to hers. In either of these positions, with the right hip movement and a bit of attention to where your penis is inside her vagina, you can hit the G-spot and move up to the cervix and back down, finding which spots she enjoys most. I find it most pleasurable to keep my torso straight, but by trying the variations you and your partner may find a new sensation you love.”
– Excerpt from Beyond Satisfied by Kenneth Play, Chapter 13: Vaginal Penetration, Side Angle