Before Coming In:
I'd have both shave 2-3 days prior to avoid razor bumps.
Have both do enemas before coming in that day.
Have both take showers before coming in.
Encourage them both to take naps before coming in.
Then drink some coffee before coming in.
On the way in, tell them to sing to warm up their voices.
While on set/before the scene starts:
Have both pornstars eat something before starting. Have food ordered in. Pamper them a little on set prior.
Have both pornstars take a shower again, to know each other is clean/smells good/fresh.
Have both brush their teeth/mouth wash and take mints before the scene for fresh breath and to encourage more kissing during the scene.
Have both watch/listen to some porn while putting on makeup, clothes and stretching. Gets them in the right mindset plus loosens them up.
Have them both read over their lines again and phrases to randomly insert during the sex.
Right before the scene, have each rub edible flavored lube lightly on.
Have both drink some water prior so they feel hydrated and their throats are clear for any dialogue.
Rehearse the scene, go over camera location and what your expecations are, and start shooting.
During the scene:
Guide the transition and pace of the film like a music conductor.
After the scene:
Pay the pornstars, clean up the set or get ready for the next one.
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