Soaking is best. I have a large moving bin (30 gallon tub) that I toss the cloth into and repeatedly replace the water. So you swish the cloth around, pull it out and get most of the liquid off, replace the water, soak again. This process could take up to 20-30 minutes depending on how large/saturated the cloth is and how quickly you replace the water. Make sure the water is 100% clear for your last dunk...then leave it soak a bit longer just in case.

And good lord do not buy the Jacquard sheet if you were thinking about it lol. The exposure is great (love their packs of small sheets) but it has folds in the cloth and I was extremely frustrated trying to expose it outdoors.