Lots of excellent advice.
Oh, and I forgot to mention that I will also slowly work up the pressure of the water and then start using my thumb over the end of the hose to create a spray before ever putting a nozzle on the hose.
I have cheap $3 brass nozzles from WalMart on the ends of my water hoses that I can quickly adjust the spray.
One of my horses likes a pretty heavy spray on his chest and that's where it ends; I have to lighten the spray for the rest of him and I sort of mist his tummy.
Another one doesn't like a heavy spray anywhere.
The other two don't care what I do for the most part unless they've got skin allergies and the heavy spray hurts.
Point-being the 3 yr old may not now or ever be comfortable with a a heavy spray hitting him. Since, as someone else mentioned, it is us humans that have decided horses need baths, we should accommodate them as much as we can while still teaching them to accept a bath in a mannerly fashion.
I do not use a water hose on anyone's face --- ever. It's a pain but the horse should not be subjected to being made to feel like he's going to drown, lose his eyesight and his hearing all at once by having a water hose flailing water around his face.
agree with letting the horse be loose, so he doesn't feel confined. Granted all horses should probably learn to stand in cross-ties but not for bathing when they are green.
My horses are all older, well-seasoned and will stand in cross ties but when I bath them, I bring them out in yard, drop the rope and nobody moves<-----that would be a yard full of grass and by moving I mean no one puts their head down to try and graze or walk off. They may do some weight shifting and head swinging going after a fly but they are content to stand still because that's how they have been taught.
Hope all the great posts are helpful