I never used milk. It's hard enough to drink Kava tea but adding milk would send me straight to the vomitorium. Then back for more. When I make tea the traditional way, I use coconut water. But I mainly do that to make the kava tasted better. I use like 3/4 coco water to 1/4 reg water. If you want to go whole hog to this. Put the kava in a blender, add liquid at about 130 degrees. Blend it for a minute. Then dump it in your strainer. The temp will have come down to 120 or so. Now knead it. Blending is good, 120 degrees is good so you are doing the maximum possible to extract kavalactones. When you are done, add half as much liquid to the remains and squeeze again. That's called a second wash and insures that you get your moneys worth.
P.S. I just put a tablespoon of micron in tiny dixie cup, went to the bathroom, added water, and stirred with a small chopstick. Gulp, gulp, gulp and I'm back at my desk. That's why I do micronized and I'm sure instant would work too. It's convenient for how and when I use it.