I use a label maker also, but I don't put it on the carto--I wrap it around the condom that goes around the battery end. I make sure that the tape/label is long enough to slightly wrap onto itself so that it does not peel off, yet it is very easily removed if I no longer need that particular label.
I am somewhat OCD also about keeping stuff organized and this is the easiest way for me. All of my cartos are separated by flavor/color in my carto box. I also have a section for extra condoms/plugs. My juices are all set up in alphabetical order so I can find them easily, but they are also set up so that large bottles are alphabetized separately from the smaller bottles.
As soon as I finish
vaping a carto and it is empty, I put the battery end condom or .... plug back on/in it and put it in its place in my carto box. That way, when I am ready to refill, I only need to take out the plug and insert syringe, refill and then take a condom from its section and replace it. (Each flavor has its own section for full cartos and another section for empties.)
If the carto is not empty, I put both condom covers back on and put it back into the carto box, but either turned a different way than the others or standing up, so that I know that particular carto has been slightly used but still has some life in it. That is the carto that I will pick up first when I want to
vape that flavor again.
Maybe I need help.
