11 Steps to Bath Your Horse After a Ride (got info of web)

1. Untack your horse and find a place to bathe him.
Said place must have a hose and a place to tie your horse. Then, tie him up.

2. Locate a sweat scraper, a sponge (optional), and a bottle of shampoo.
It doesn't have to be horse shampoo - in fact, Suave Naturals works great

3. Turn the hose on very low.
So you don't spook your horse with a sudden blast of water.

4. Let your horse get a good look at the hose
so he has an idea of what that thing is that's making him all wet.

5. Gently trickle water down the horse's sides, neck, and legs.

6. Lift up the horse's tail and wash down there (just to get it over with)

7. Squirt some shampoo on your hand and gently rub it onto the horses side and neck. Make sure you really rub it in.

Right or left - start with whichever side you want.

8. Rinse the horse very well, then scrape the excess water off with the sweat scraper.
Repeat this step until you no longer see any white soap suds when you use the sweat scraper.

9. Repeat steps 7 and 8 with the other side and the legs

10. Lead the horse around for a few minutes until he is dry

11. Put him back in his stall or paddock

Tips:
1. If your horse doesn't like water, put a blindfold over his eyes or try to let him drink from the slow flowing hose.
2. Give your horse a massage while you rub the shampoo in, it will really relax him.
3. Keep rinsing until you don't see the lathery mixture of shapoo and sweat.
4. You may want to use a curry comb to smooth out your horse's coat afterwards.

Warnings:
1. Don't let him get his legs wrapped in the hose!
2. Some horses are scared of, or don't like water. You may need a blindfold and/or extra handlers.
3. You shouldn't do this every time you ride - it will damage your horse's skin. Sometimes just a quick rinse is enough
4. Don't spray the horse's face with the water!

Things You'll Need:
1. Horse
2. You
3. Halter
4. Lead rope
5. Mild shampoo
6. Sponge (optional)
7. Blindfold (if needed)
8. Sweat scraper
9. Hose
10. Towel to dry his legs especially around tendons

Got information from:
http://www.wikihow.com/Give-Your-Horse-a-Quick-Bath