If I don't care about getting oil on things, I use a spray bottle with vegatable oil. If I DO care, then I use soapy water. If I want to save the wasps, I use water and after the wasps can't fly, take down the nest and put it in a jar. After they can fly and have regrouped on the nest, put the lid (with air holes of course) on and take them where you want them. Dump them on the ground and run. Come back and spray with water again and shake them off on the ground. Put the nest up where you want it with some kind of quick drying glue or fast epoxy with something to hold it in place. After it is solid, remove whatever you have holding it and the wasps will dry out and move back in.