I lube the cables on my Harley every 6-12 months depending on the cable. I've tried all sorts lubes, what I've settled on are the dry teflon lubes, the Blaster Dry Lube w/ Teflon for the past couple of years. I don't use a cable lube tool, I just wedge the straw between the cable and housing, press a rag tightly around it, and squirt. The Blaster stuff has alot of carrier in it so it flows pretty freely, doesn't take much to see it coming out the other end of the cable. It evaporates quick and leaves teflon powder, I figure that's a good match since the cables are lined with teflon to begin with. The overspray cleans up easy since it's just teflow powder once it dries.
FWIW I stay away from wet lubes, I don't like the oily stuff migrating away from where I put it and attracting dirt. I use a dry wax lube for things where I don't want teflon powder, like chains and stuff, but teflon powder always on cables.