I also hit the button and wait for the "crackle" before I draw. I take a long slow draw, so long sometimes that I hit automatic cut-off when the tip blinks 5 times. Hasn't seemed to hurt my batteries because they're still going strong after a month and a half of use.
I'm way too shaky to prime my atomizers with a dropper. I top off my cartridge level with the top and gently insert it upwards into the inverted atomizer until it makes contact. Then I withdraw the cartridge noting that the excess
juice is gone, top it off and do it again until the cartridge comes out with the filler saturated but without excess
juice. Then I plug up and enjoy.
I tried the "correct" method of priming but always ended up shooting juice into the atomizer body instead of the wick.