take this with a grain of salt since I’m not 100% sure but unless you are in a higher position than them you could potentially come off as annoying + having a “better than thou” attitude even if you have good intentions 😢😢so it *might* be best to let an ssv or the sm know so they can politely correct them because then it can be viewed as a teaching moment which said partner will probably understand & appreciate. ofc if you’re not in either of those positions you can still correct them but a lot of people don’t like criticism from others in the same position as them. just varies from person to person i think. also im just assuming ur a barista so if ur an ssv or sm correct me but if you are either one of those you shouldn’t have any issues correcting them if you’re nice about it. something like “hey I noticed your technique when doing ___ and i think you’re doing great but it’s easier and more efficient to do [insert correct way here] and that’s the way the company would like us to do it”. hope I don’t sound silly but good luck to u 🎉and just remember #1 thing is be polite and patient because partners want to feel respected and not feel like they’re stupid for doing something incorrectly

Challenge them to a dry cap contest. Give pointers after you win.

“I’ve found an easier/faster way to get great foam , can I show you my secrets/are you willing to try another way, you may like it better”

You never know, maybe they’re struggling and frustrated not being able to make quality foam but embarrassed to ask for help , might be grateful