From what I've read, you want to keep your atomizer wet. Don't let it dry out by sucking on a near empty cart. Some have said they tasted a burnt taste when this happens. Just remember to add a few drops of liquid if you've been vaping for a while. I'm not sure on the regularity, but every so often you can clean your atty by either soaking it in warm/hot water or cola (rinse after) then blowing it out and letting it dry overnight. I'm kind of lazy, so I clean my atty every other day. I've only been vaping for three days though and working on my first atty.
I've also noticed that the term "your milage may vary" occurs often. You could have had a bad atty to start, but caring for your second may help prolong its life. Again, I'm a newbie too, so I could be wrong.
Foltzy