Hi,
Spend more time vacuuming the rug than any other cleaning operation. It is worth trying to elevate the rug off the floor on a dusting board (essentially mat that has lots of holes in it) as this will quicken the dry soil removal. Like Mark said, keep vacuuming it face down untill the amount of dust falling out of the rug is small then turn it over and vac the face a few times.
Test, test and test some more. If you test properly it will never become your rug. eg We have seen one example of dye stability on one edge of the rug, but not the same colour on the other side (vibrant pink dye on a hand made Maroccan wool). We allways test all the colours on a few different areas of the rug to ensure stability across the entire face. Test your cleaning mixture and your rinse mixture, i guess in theory you should also test both mixtures at the cleaning temperature (i think this is going a bit too far and have never bothered)
Personally, i would prefer to use a wand on rugs like this as they put out more water. We have found that upholstery tools (intentionally) have a vastly reduced flow rate and dense pile wool rugs really need that bit more rinse. We dry at 40-50% rel humidity @20-25°C and have never experienced problems with drying times due to overwetting. A prominet CC figure said at a training event that these rugs can be submersed, its not really about how much water you use, more to do with how you dry them.
Hope this helps
Graeme
Access Cleaning Solutions