If you are new to DA polishing, here's a few tips below. Much of it relates to polishing paintwork, B pillars are simpler and some things won't apply but you get the gist of it hopefully.
• Assess the condition of the paintwork first in good light, so you know what level of correction/swirl removal is required
• Prepare the paintwork prior to polishing - tar remover, iron remover, claying etc, to ensure it's free of all bonded contaminants.
• Only polish on a perfectly clean car
• Tape up all trim with low tack masking tape
• Start with the least abrasive pad and polish combo and step up as necessary. Choose your polish first. Then the lease abrasive pad, if more cut is required step up to the next pad. If a more abrasive polish is required use that again starting with the least abrasive pad.....and so on.
• Start with the correction/swirl removal polishing stage first using a cutting/polishing pad then follow with the refining stage using a finishing pad.
• Moisten the pad before applying the polish
• Apply a few dots of polish around the perimeter of the pad and a dot in the middle. Do not saturate the pad with polish. Similarly do not use too little.
• Once you've primed the pad with polish make sure you place it on the paintwork before switching on DA, otherwise the polish will fling off everywhere.
• Always sling the DA cable over your shoulder otherwise it can drag/trail across the paintwork causing marks (just as you are trying to get rid of them!).
• Do a test spot first to see what is required to remove swirls etc.
• Take it slowly and work a small area at a time. Split larger panels up into smaller manageable areas, say 1.5' x 1.5' areas.
• Use moderate arm pressure - too light and it will have little effect, too much and you will get build up of too much heat and may damage your pads and possibly the backing plate.
• Use medium speed - too low a speed won't achieve anything. Many people start off on too low a speed.
• Move the DA slowly over the area to be polished. Moving it too fast won't be effective. Move the DA across the work area horizontally back and forth, slightly overlapping as do, then move it vertically up/down, again slightly overlapping movements.
• Stop, remove polish residue and inspect at regular intervals to see how you are progressing and what further action is required.
• Use a good LED light source to check your progress close up
• You might need to do several passes to achieve the required correction/finish
• Clean your pads on the fly. Do not add fresh polish onto a pad with built up polish residue.
• After polishing use a good IPA or Panel Wipe to remove all polish residue before going on to seal/wax the car.
• Have regular cups of tea!
Some great tips and vids here
http://www.autogeek.net/dual-action-polisher.htmlhttp://www.autogeekonline.net/forum/how-articles/20135-how-clean-your-foam-pad-fly.html