I`m writing this guide as I feel obligated to talk about it. I sell lots of trumpets on ebay and one thing which bugs me the most is that there is a wrong idea around the cleaning of the valves. Yes valves should be maintainted , cleaned by cloth and oiled/lubricated BUT NOT POLISHED ! PLEASE DO NOT ! AGAIN DO NOT POLISH THE ACTUAL PISTONS !!! Let me explain by polising of the actual piston you are damaging the surface by removing the nickel plating from it ! This surface is very important for piston to move smoothly inside the valve casing. After polishing like this piston may even scratch the inside of the valve casing and it will be getting stuck or will get sticky so basically polishing of the pistons decreases lifetime of the valves. Valve jobs are pretty expensive and believe me you don`t want to go in those costs so DO NOT POLISH VALVES FOR YOUR OWN GOOD !

Another thing is about trumpet finishes. DO NO POLISH LACQUERED FINISHED INSTRUMENTS also DO NOT WASH THOSE IN HOT WATER when cleaning instrument as lacquer may start to peel later. Wash it in warmer not to hot water if you must wash or give it to a brass specialist who will clean it chemically or ultrasonically ( not an expensive job and it`s worthy ! ) 

Silver instruments may be polished by special cloth which you may find on ebay or at your dealer store or you can simply purchase a liquid for silver cleaning at the hardware store. If you have a gold plated instrument or mouthpiece ( not gold lacquer ) and you see darker spots developed when it was unplayed for a longer period of time you can also use that liquid or cloth for silver. It will do the work.

Finally if you are always in a hurry and have no time to polish or clean your horn please clean at least the leadpipe ( first pipe where the mouthpiece goes ) and if you have little more time also tuning slide. Once a week will help your horn leadpipe to live longer. Just use a cleaning snake and flush it with water. This will help you in a long run to get an additional mileage out of your horn.

Last advices. Wash your mouthpiece(s) OFTEN ! Remove water from the horn after playing as well as from all slides and valves. Lubricate valves after playing so instead of water oil sleeps there :-)

Good luck . I hope those advices will be helpful to you. Keep blowing & ebaying. Trumpet Powerseller Hotdeal1smoko