The way we do it is, fill bucket, pour in your soap or whatever you use. Soak your aplicator. Fill small bootle out of bucket, place in belt holder or bottle holder on the side of your ladder. Use bootle to keep your aplicator wet. We use Monsoon aplicator, holds enough water in it to last an average house (2 bed semi).
This way, you don't need to drag a bucket around all day.
Good for mainainance cleans, first cleans though, you need to work wetter, so use the bucket.
Also, look on youtube for "Wagga" He gives good tip about these things.
Hope this helps mate.