Before one of my trips to Wales I dunk my Meindls in a bowl of water for a few minutes to get them wet. Of course, if I've just been on a day walk and got them well muddy, I wash the mud off with a jet on a hosepipe, so they're already going to be wet.
When the exterior wetness has dried off, it doesn't take long, I spray the boots with Meindl waterproofing spray.
I then leave them a couple of days to dry.
Then I do them thoroughly with Meindl Sportwax, my preferred method being with my forefinger in an old rag.
I'll go along with what the others say about leaving them overnight.
During my trip, on the rare occasions it is dry (I've been lucky on the last two!) the boots remain waxed. When more usually the ground is wet and boggy and/or it rains, they become sodden wet lumps by the second day.
After my walk I usually spend three days or so camping, when I simply put the boots on the roof of my car to dry or in the porch of my base camp tent.
After I've returned home, I wax them when I'm certain they are completely dry.