ah...easy one. and i will keep it G rated.
i have plantar fascitis, which flares up occasionally. so i have very tender arches! a lot of people do, especially gals who wear heels or stand a lot.
the secret is gentle pressure, no tickling, and some nice fragrance free cream like vaseline intensive care. no special oil needed.
get your patient to relax, i.e. lay down on a couch. you sit at the end with footsies in your lap. put a hand towel under the footsies.
put a big dab of cream in one hand. rub between your 2 hands to warm it and spread all over the foot, one at a time.
start with the main knuckles on your hand on the entire bottom of one foot. then curl your fingers and use the middle joint, repeat many times.
use your fingertips to gently push the sole of the foot apart from the center, heel to toe.
then gently tug on the end of each toe to "crack" it. GENTLY!!!!
rub all toes between both palms, like you are washing your hands.
use the heel of your hand to finish up the sole again, pressure from heel to toe, heel to toe.
do the other foot.
collect your reward.