this is a brief run down on the two bucket method.
it is basicly used to
reduce the damage caused to paint when washing. back in the day a good old sponge was good enough but to keep your car in the best condition this will help loads and cut down on work in the future.
first things first, throw your sponges away and buy a decent lambswool mit from a multitude of places. the lambswool mit draws dirt particles into the fibres so they aren't being pushed around the surface of your paint. with a sponge the dirt has no-where to go so acts like an abrasive as you wash away. also buy two buckets.
fill one bucket with a decent shampoo
NEVER USE WASHING UP LIQUID and warm water.
fill second bucket with clean water. it helps to have different coloured buckets to help you remember which is which.
hose off the car to soften/remove loose dirt
when you wash put the lambswool mit in the shampoo bucket, wash a panel, starting with the roof. then after each panel, put the mit in the clean water bucket and clean it off.
then back in the shampoo bucket, next panel, always working panels from top to bottom.
i say have different coloured buckets as by the time you're halfway through the car both buckets will look soapy!
hose off and pat dry with a waffle weave towel and then do your polishing/waxing.
it takes more effort and seems like alot of hard work but when you see the residue left in the clean water bucket at the end, you'll see all the filth that you'd otherwise be sloshing all over your car.