What You Will Need:
* Small freezer bags - one will make 2 cones
* Scissors
* Scotch tape
* Twist ties
Step One: Cut the freezer bag into squares
The size you make the cones is up to you, but you don't want it too big or it will be hard to handle. It also depends on the size of the freezer bags you start with. I usually cut the bags into 6" squares. Use a straight edge to make sure your corners are 90 degrees, as this will help in the actual folding of the cone.
Step Two: Make a funnel shape out of the square
This is not as easy as it sounds. The plastic is very slippery and you will want to wrap the square around itself in such a way that it completely overlaps (leaving no open spaces for the paste to squeeze out). At the same time, you need to leave a small hole at the bottom of the funnel, just large enough to allow the paste to squeeze out without difficulty. This might take some practice and becoming comfortable with the consistency of your henna paste and what size hole is required to get an even flow.
Step Three: Taping the cone
After you get the funnel exactly how you want it, you will need to tape along the side edges where the plastic overlaps. Be careful not to move the plastic when you do this, or you will have to start over again. It's good if you already have a few small pieces of tape ready instead of trying to get it from the dispenser at this time. Tape all the way from the bottom to the top of the funnel.
Step Four: Filling the cone
Now you will want to put your prepared henna paste in the cone. Using a small spoon* seems to be the best way to do this. Carefully place a spoonful of henna paste into the cone, and press your finger lightly against it (from the outside) as you remove the spoon. Repeat until the cone is about half full. Filling too much can cause the cone to be hard to handle and burst due to excessive squeezing. *Note: Never use anything metal with your henna paste - use plastic or glass.
Step Five: Closing the cone
One who is experienced in using the cones (or even in using decorating bags) can usually just twist the end of the cone and apply the paste. This can become quite messy for one that is not used to it, though, because not applying the right amount of pressure and squeezing the proper way can cause the henna to come spilling out the top. The best thing to use in this case would be a twist tie. First, twist the bag itself in the direction of the overlapping fold. Then secure it with a twist tie, and you're ready to go!
And that's it! It takes a little practice, but making your own henna paste and your own cones is less expensive, and creates beautiful henna art without a lot of work.