1. Keep your contacts clean; especially of juice. Find yourself a box of pointed cotton swabs, and use them often. And if you top-off from the battery-end, use a swab on the contact after every top-off.
2. As for recharging frequency, avoid the two extremes. In other words, avoid fully discharging your batteries (to the flashing L.E.D. cut-off point), and avoid charging them too often. Try to use your battery for about half as long as you know you could if you were to push it. This tends to be about an hour, to an hour and a half, for me; and requires that I keep three batteries in rotation.
3. Don't leave your batteries in the car, or anywhere else that they could be exposed to heat.