Are you using atomizer + carts? Least popular way to vape. Most people use cartomizers, at least for their favorite juices.
A cartomizer is a self-contained 1-piece disposable cart+atomizer. They hold more juice than carts, need juice less often, provide a more consistent vaping experience, keep your flavors totally separate, and there are no attys to keep clean. I can get 10 days use or more out of a Boge. I got 14 days out of my current one (and that's a month for me because I vape another model 1/2 the time so that 28 1/2 days on this Boge). Downside - you need to keep them damp else you singe the stuffing and add bitterness to the flavor (a little bit of singe is not a great problem for a tobacco flavor but can ruin a sweet flavor). And they have limited lives. they cannot be restuffed. Some people clean and dry them to get more use but for simple cartos like Boge that cost under $2 each most don't bother trying since the results can be inconsistent.
If you have never filled cartomizers you may want to try try the standard resistance Boge ones first - they will be more forgiving as you learn to keep them damp. The 2.0 ones run hotter and may be a bit trickier to learn on but these are the most popular ones on Ego.
I have excellent results with Boge cartos and thin clear juices. I use PG juices with 20% or less VG and I avoid juices that seem to drop a lot of flavoring sediment to clog the carto.
And if you don't have a drip tip - you can use a drip tip to test juice on the atomizer without filling a cart. A 9.2mm diameter 510 width atty uses a 510 drip tip and a fatter Ego atomizer uses an Ego drip tip. A plastic or delrin 510 drip can usually also be used as an easy to remove mouthpiece on a Boge cartomizer.
How I fill
Make a Boge carto take 18 drops of juice (per ml capacity and they are 1ml cartos), wait 15 seconds, slowly add however many more (usually 1 to 6) it will soak in easily (I hold tissue on the threaded end hole and tilt the carto, drip down inner wall). Then clean it up. My cleanup includes the threads, then open end down I puff into the threaded end to clear the air channel, then while still open end down I touch soft tissue to the top of the stuffing (makes it less likely to leak). Then let it settle on different sides for a total of 15-20 minutes (enough time for 20% or less VG juices tp dampen every bit of stuffing). Then vape. As you vape, if the vapor or flavor seems off or light or dry, or if the carto is getting unusually warm, it may need juice. I also look at the stuffing and if it looks white on top again, you could add some juice.
Thick juices are hard to use in cartomizers. They spread slowly and move slowly through the stuffing so they can fail to keep the coil area damp enough then the carto will singe.
And you can use carts or drip tip for thicker juices. A couple of people say they can use 100% VG in dual coil cartos. And there are reservoir cartomizers that may be able to use up to thinner 50/50 juices. But I recommend you learn the simple popular Boge ones first.
You posted this advice elsewhere and I followed your advice. Got myself 15 Resurrectors from CCV and after a day of use... I'm convinced the step from eGo-T carts to cartomizers was a good one. The Resurrectors are great, more vapor, more consistent vape... couldn't be happier. I still might step up to a tank, but for now, I will be keeping CCV busy. 
