Others have made similar suggestions, so I am just adding my own voice to that.
First, invest in some cleaner burning e liquid, try provari fuel
ProVari Fuel E-Liquid or Heathers Heavenly Vapes
E-Liquid Flavors : Heather’s Heavenly Vapes, Top Quality Custom E-Liquids Both have good
juice that doesn't junk up
coils so badly as other places.
Second is not to put too much wattage on your coils, just turn it down some from where you are now.. vape the lower end of whatever wattage range your coils fire.
Third is to build your own coils.. go ahead and get one of those coils building kits, and try your hand at it giving yourself plenty of time to learn. It's easier than it looks, I would recommend staring with a
tank like this one here to learn on, it's cheap and so very easy to build its unbelievable, plus the flavor it produces is great.. then once you have the hang of it, you can graduate to something a little more difficult.
$8.54 Nectar Styled Genesis RTA Rebuildable Tank Atomizer - stainless steel + POM / 22mm diameter at FastTech - Worldwide Free Shipping
That way, even if you don't build all the time, you have the knowledge to fall back on. I'm a woman who kills plants and I can build with no problems, so you can learn too! It's easier than it looks!