This is my basic henna paste, only for use on skin..I wouldn't use this on canvas or on any wood products etc, and I'm not going to give away my formula for that...I'm slightly paranoid lol...
Put your henna powder into a glass bowl, or plastic if you haven't got glass, preferably with an airtight lid, but you can use clingfilm if necessary.
Add a good amount of sugar...the more sugar, the stickier and stringier the paste will be. Note - Moroccan henna doesn't need much sugar as it is naturally stringy, but if using Rajasthani or Pakistani henna you'll need quite a bit.
Add lemon juice bit by bit until you can no longer see the green powder, and it is a smooth paste.
The paste will preferably be toothpaste like, and will be liquidy to the sight, but smooth and medium thick when mixing with a spoon. Add a few drops of essential oils, e.g. tea tree, to the paste and mix thoroughly.
If the paste falls slowly off of the spoon/spatula then it will be lovely and stringy when you use it inshallah. Cover the paste and leave in a warm - but not hot - place for 10-12 hours or until the very top turns a dark brown. Then mix the paste again, and put it into you cones/bottles/syringes etc...
Have fun trying this inshallah, it's very easy, and you can find the recipe anywhere...but one more place won't hurt lol x