I don't do anything very special. I apply Boeshield T-9 and spin the cranks for a minute or so before thoroughly wiping the chain off. I do this every few days on tour.

I also try to avoid cross chaining, mostly using gears with a fairly straight chain line. I try to shift smoothly. I use medium quality chains similar to what came on my bikes. I start thinking about replacing them when 12 complete links measure 12-1/16" and make sure to do it well before they measures 12-1/8".

I like to say it is my silky smooth spin that makes my chains last, but I really do not believe that to be true.

I have to say that I am kind of puzzled when folks say that their chains last only 2 or 3 thousand miles. My chains have always lasted much longer as have those of my family and friends whose bikes I have maintained. I know that the three of us who did the trans america together all had the same chain for the whole tour and then used it for a long time after.