You are putting no more than 2-3 drops (i recommend only 2) into the metal wick of the atomizer. The metal wick in the atomizer is found at the opposite end of where you would screw the battery in.
Depending on the model, some atomizers you can clearly see the metal wick (in other words, they are exposed) and in some models, the metal wick is enclosed with metal.
By dripping directly into the atomizer, you will get the maximum vapor that your
device can produce...or close to it at least.
The only downside i see by only dripping into the atomizer, is that you will find youserlf keep dripping into the atomizer after a couple of puffs.
I recommend filling up the cart and putting 2 drops into the atomizer. That way you can get the initial superb vapor production and then keep
vaping until you see a loss in vapor. Then keep dripping into the atomizer until the cart. is almost empty. This way, it will keep your atomizer fully lubricated and at the same time use up the liquid inside your cart.