i normally (try to ) use diluted shampoo in a bottle with a nozzle. I lift up the tracks and put the shampoo on my scalp (through the net). Then I lightly rub the scalp/net with the pads of my fingers. I also use the shampoo on the weaving hair. Rinse thoroughly.
Then I would apply conditioner the same way. Depending on the type of weaving hair I was using, I would DC both my braids underneath and the weaving hair. Rinse thoroughly because with the net, it's easier for build up to occur (IMO).
If you have a detachable shower head, that helps a lot.