Everyones painscale is different. For me- a 10 is childbirth .
None of my tattoos have felt like I was pushing a 10lb 7 oz baby out of my vagina again, but some people do state that some tattoos are a 10. Everyone will have a different idea of pain based on their lived experiences. ( compare someone who has only stubbed a toe vs someone who has broken a bone for example )
If you want easy peasy pain- go arms. outside of arm is a piece of piss. Inner forearms more sensitive than outer, but still nothing hard to deal with (very low pain scale for me, more of an annoyance than pain).
Eat a decent meal the day of and the night before, be well rested, well hydrated, don't be loaded on drugs or hung over from a night on the sauce and you will be fine.
As far as the design goes, they may just use skin breaks instead of actually using white ink.
As far as communicating with the artist- research who is out there and see what they prefer. Some prefer email, some in person, some say fill out an online booking request.
Do the research and you'll get the answers you're after.