Birds need baths.  Even reluctant bathers need to have exposure to water.  Every bird is different and each bird will make its own decision about how they want to bath.

I used to spray Rita, my cockatiel with a gentle mist from a spray bottle.   She loved these baths and would hang upside down with her wings out, getting drenched.

I would not use a spray bottle on my Senegals.   I tried a very light and gentle spray with Babylon and she immediately flew at the bottle and tried to dismantle it and my finger.   Water can be a trigger for aggressive behavior for some parrots so you have to be careful how you encourage bathing.  All of my Senegals choose to bath in their water dishes in their cages throughout the day.

Kiri likes to have a soup bowl placed in her cage.   She learned to bath this way from watching the Senegals.  She will get in the soup bowl and make a huge mess but she also gets a good bath.

When we remodeled our house, we installed a rain tile above a shower seat.   This is where Phinney takes her baths.   We had to redo the bathroom any way so why not make changes that easily accomodate showers for the parrots?  The top photo shows Phinney on her perch in the shower.   In the second photo she is on top of the shower door and the rain tile is visible behind her.

I am currently working to acclimate Kiri to the shower.  She sits on the top of the door and watches Phinney shower.  Right now, Kiri will sit on the perch but has yet to tolerate the water.   We are working very slowly, using Phinney to model the behavior “take a shower” and bringing Kiri into the space as her comfort level allows.