Using the cones to store ready-to-use paste:

Mix a batch of henna paste per your usual methods; bring it to the consistency you typically use for cone or squeeze-bottle application.

Transfer paste into the new cones, leaving an inch or two of empty space at the top of the cone. It is important to not get any paste near or on the edge of the top...if you do, it will not seal properly. I use paperclips to affix the cone, opened, inside a plastic soft drink bottle that has the top cut off. Then I put my paste into another ziplock bag, snip off a corner of the bag and squeeze it into the cones carefully. This makes it easier to prevent any paste getting onto the top of the cone.

Finally, seal the top of the cone. Obviously, the book method won't work here as the paste would ooze out when the book was closed. So, lay the cone on your table with about 1/16" sticking over the edge. Place the metal ruler's edge along the top to hold the sides together, press down, and run the lighter flame along the edge, melting the sides together.

Voila! If you're going to use in the next couple of days, allow them to sit out for a few hours, then toss into your refrigerator. If you're not going to use it for a week or two, just toss 'em into the fridge. Yes, I've had henna paste stay active in excess of a week using this method.

To use, simply snip off a tiny bit off of the tip. Keep snipping TINY bits off until you get the hole size you desire. Other than that, use it just like any other cone.
 

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