“If your lord wishes to bathe and wash his body clean, hang sheets round the roof, every one full of flowers and sweet green herbs, and have five or six sponges to sit or lean upon, and see that you have one big sponge to sit upon, and a sheet over so that he may bathe there for a while, and have a sponge also for under his feet, if there be any to spare, and always be careful that the door is shut. Have a basin full of hot fresh herbs and wash his body with a soft sponge, rinse him with fair warm rose-water, and throw it over him; then let him go to bed; but see that the bed be sweet and nice; and first put on his socks and slippers that he may go near the fire and stand on his foot-sheet, wipe him dry with a clean cloth, and take him to bed to cure his troubles.”
John Russell, Boke of Nurture
Does your bathing routine involve a bushel of fresh herbage and half a dozen sponges? Hmm, looks like the Middle Ages just schooled you in bathing.
How to Wash Your Head, 1612, here.