You can use some body paint (check in an art or make up shops) and draw beautiful shapes on your partner's body.
You can for instance lay down and let your partner paint on you or the other way round.
You can as well sit facing each other to do that.
Don't cover your whole body with paint of course ;) - Be subtle.
These are like winks of positive energy you give to each other.
It is a way of saying: "I love your body and I decorate it with beauty"
You can as well use sacred powders used in india for bindus. You have them in red, orange and white for instance.
(these are the colours you see saddhus often wearing with all sorts of symbols on their forheads)
You can take some of that powder, mix it with a tiny bit of water and use your finger or a small brush to initiate your partner's body.
You can as well write words on each other.
Here are some ideas:
You use each other's body as a mantric support and energise each other's body and mind by doing so.
If you want to write names in Sanskrit script go back to my site and check sanskrit mantras.
You can learn them or directly copy them on your partner's body.
When you write a god or goddess name on your body, it is a way of reconnecting with an absolute universal reality.
Using divine names realigns your mind with a perfect plan and opens new doors of energy through your being.
I would start with just shapes and then, try a word in english.
If your partner likes it, you can then start using a non personified sanskrit word like shantih.
After that, you can go further by using one of shiva's or shakti's names for instance.
If for any reason you feel uncomfortable with using a god or goddess name, no problem, ok? ;)
You can stick to shapes and words in English for instance.
They have as well the power to open new energy doors throughout your body.
Enjoy your tantric delights!