Waxing your depower line (the line that goes through the bar).
I have been doing this for a while and it dramatically prolongs the life of the line.
I recently started using bowstring wax for bow and arrow bow strings.
The stuff is great. Even in cold weather it stays flexible and lasts longer than other wax. You also do not have to melt it to apply it to your lines.
Just rub it on directly and then apply a glob to a non porous rag and rub it into the line aggressively heating up the wax and forcing it into the fibers.
I use this stuiff that I found at Big5 Sporting goods.
It's only 4 dollars and one stick is enough for 4 naish line sets with double depower line. (trim line).
While it has a sticky feel to it it does not jam your lines. Water slides on it very very well. It also adds very little thickness to your lines.
Works well with my Naish clam cleat (the toothy thing you lock your line in). Not sure how well it works with the bar lock that slides up and down above your bar. I take that piece of crap off my lines.