I've been asked to explain an internal massage, so here it is.
So, making sure you are comfortable, and aroused, you lay down naked, you can be covered if more comfy that way. You just need to not be restricted by clothing, let your body be free.

I'd test how aroused you are, naturally ready to gently kiss, lick and suck on your clit until I can feel a suitable warmth and wetness from you.
I begin by using a fingertip to just gently stroke your labia up and down and occasionally circling your clit. I’m trying to spread your lube around the area and onto my finger, slowly going further as I feel you relaxing. I then start circling your introitus, vaginal opening. This is the first part I gently massage. I’m feeling for slight grooves and curves, do they harden? Or do they remain as is. I’m also watching your face. I’m looking for signs of excitement, enjoyment. Also I look at exposed skin, I’m looking for goosebumps. I the slightly insert my fingertip, circling inside you, once again, feeling for bumps, etc, until I come across a ring. It’s only noticeable due to your heightened sense of arousal, and my heightened sense of awareness. This ring is the first of several inside you I will massage. So I will circle this, many times, observing you, and while circling slowly going forwards into the next groove, feeling for bumps, until I reach the next ring. As I go deeper, yet I am not in deep at all, I make this sound like your vagina is the size of an oval, but these are small, subtle movements, I do go back and re-work what I’ve previously massaged, still feeling for subtleties, and observing your face and skin. As I go forward, I start feeling the outer surrounds of your g spot, which I will start seeing a change in your face and skin. Your body temp will start to rise, your breathing will change, and the area will change. I’ll continue to massage as I have been, constant pace, gently, circular, going back and forwards, and every now and then, apply a little more pressure over your g spot. All those spots I stimulated earlier, I will go back and check to see if they are still aroused, then back to massaging the current ring. I won’t be focusing entirely on your g spot, as teasing it is what the massage is all about. Your whole vagina will be massaged and explored, right up to the last ring, up around your cervix. At some stage during this, any muscle tension, frustration, will come to an end as you climax as you explode, and you will explode. I will become selfish at this point and kiss you, because I love to kiss a woman after she has orgasmed. I love the sloppy effort, and I will kiss your back down to both your breasts, down to your belly and down to your clit before I gently have my fingertips going all over your body, I want to feel where you are clammy, sensitive on your outside, where you still have goosebumps, can I move them around? etc, and that’s it