In a dream world, we would all have dedicated laundry machines for our horses, preferably in a separate room with a separate entrance. Since diving in deep with horses I've begun using our garage as a pre-mudroom. Particularly muddy boots are left in the garage. I wish we had a horse mudroom during shedding season when our coats are covered in horse hair. I hate dragging all that hair and dirt into my nice, clean house.
Here in the real world, my laundry machines are on the second floor with the bedrooms which seemed like a great idea at the time. Since the horses have to share with the humans, I've come up with a few procedures which make doing the horse laundry a bit less messy and hopefully prevent horse hair from ending up all over the clothing of the non-horse lovers in the house.
At home we wash saddle pads, fleece blankets, Baker blankets, Irish knits and non-water proof sheets. I have washed AND dried waterproof sheets in the past before I knew anything and honestly it did them no harm and they were still waterproof but I wouldn't count on that working out for an extended period.
Step one is to be sure all human laundry is totally done and that you won't need clean machines again for at least 24 hours. All human laundry is put away and the laundry room has nothing on the floor. I then dump all the horse laundry on the tile floor.
I have a good sized machine so unless we brought sheets home, our things fit in one load. We usually just have saddle pads. If you need to wash girths, they can go in the same load with the saddle pads. Just use some duct tape to pad the buckles. I like to tape the two buckles on each end together and wrap several layers of tape around them. This reduces the noise as they wash and dry and also protects your machines from scratching. If you have bulky metal pieces on any of your sheets or blankets I would suggest using duct tape for those as well. You can also remove leg straps and soak those in a bucket or laundry sink if you don't want to put them through the laundry. Dryers are particularly bad for elastic so you might not want to dry them in the machine even if you machine washed them.
Check the care instructions for your items. If you are washing things that cannot go in the dryer, have a plan for where those are going to hang. The reality is that the dryer is the workhorse in removing the hair from your horse laundry. We have an alternative solution but first you need to hang the items to dry somewhere that you either won't mind having lots of horse hair (clothesline?) or in a place that is easily cleaned up with a vacuum cleaner (basement?). I put fuzzy girths and basic saddle pads in the dryer. I do not put the Back on Track saddle pads in the dryer. I put all blankets, fleeces, Irish knits, etc. in the dryer. I have a friend with saddle pads that need to be hand washed so think about all of this when deciding what tack to use for your horse.
My system is based on front loading machines so I'm not sure if it will work as well with a top loader but give it a try.
After taking the laundry out of the washing machine and putting it in the dryer or hanging it to dry, I leave the washing machine open to dry over night. The next day I take the horse laundry out of the dryer and put it downstairs to go to the barn. I then use the hose on my vacuum cleaner to thoroughly clean the washing machine, dryer, lint collector, floor of the laundry room and tops of my machines. That horse hair gets EVERYWHERE!!!!
Then I turn to my line dried items. I vacuum the saddle pads. You can do this prior to washing but I actually find it works better for me to do it after. I run the vacuum back and forth over the saddle pad probably 20 or 30 times until the bulk of the hair is gone. For sheets and blankets I tend to just shake them out outside. I suppose you could try vacuuming but I think they need more heft so the vacuum won't just suck them up.
On occasion I have washed and dried blankets a second time through clean machines and used a dryer sheet to try and remove more hair. Of course I then had to clean the machines a second time.
For a Mattes pad or other sheepskin pad follow the manufacturer directions very carefully. Mattes pads come with special soap. They can be washed in a regular washing machine but in my experience they take forever to dry.
For medium and heave sheets and our water proof sheet if I don't feel like hanging it to dry after washing, I send them out to be cleaned. Dover Saddlery provides blanket cleaning and most barns have someone collect all the blankets for cleaning at the end of the winter. Expect it to take 4 - 8 weeks to get the blankets back from cleaning. In a pinch, you really need to just do it yourself. You can probably do a medium in your home machine and hang it to dry but a heavy would need a really good sized machine.
The other thought I have had is to take everything to a laundromat. It's kind of obnoxious to go infest public machines with all your horse hair but you've got to do what you've go to do!
It was during our first spring shedding season that Elizabeth and I became big fans of clipping our horse. When you clip in the winter it means you need to blanket your horse more heavily through the cold weather and of course if you clip on your own you make a huge mess. I usually wear a coat that is then sent immediately to the dry cleaner. I know other people who get full body plastic suits from Home Depot to wear while clipping. But the upside is that you don't have two months of horrendous shedding in the spring. We leave a decent amount of hair on our horse so even though she's trace clipped, she is shedding. But much less so than if we hadn't clipped her at all.
As for your winter coat (I have a brown one I call my medium and a black one I call my heavy, both fully dedicated to the barn and too filthy and smelly to go anywhere else) it's off to the dry cleaner. I've accumulated barn and non-barn versions of most outerwear at this point and footwear for that matter. I wait until May and off the coats go to be freshened up for the next winter which is never far enough away.