I've washed my Columbia wool stuff a few times.
I read to clean the bathtub up real nice. Use warm water, not hot or cold, and as was mentioned, a very small amount of scent free soap so as not to strip the natural oils off the wool. Gently massage the water in and out of the clothing and then rinse again with luke warm water. Get as much water as you can out of the clothes by squeezing it out, and then again, as was mentioned, lay them out on a towel to soak up some more. I put a towel on top and press down and then use that towel on the bottom for round two. Then just air dry them laid flat.
As far as getting blood out of them, this gets the bulk of it out and a blood stain mark is just extra camo in my opinion.
I'm going to add that as my wool pants were to large, the last time I just threw them in with a load of clothes in the washer on warm wash/cold rinse, and then into the dryer after, removing them before they were completely dry, and then air dried them the rest of the way, which produced the same end result as all the PIA stuff above, lol. They did shrink the smallest amount, but I was hoping they would anyway!
I'm thinking the more time consuming route would be a good idea if you have expensive 100% wool clothes like KOM or something.