Jac bottles will make the joints in your fingers ache. Cones are easier on your hands.
Carrot bags (piping bags) are a convenient tool to precisely apply henna mixes, and to freeze leftovers.
Use disposable pipettes for filling cones.
Syringe, nitrile gloves and tongue depressor for use in filling cones with gilding paste.
Nitrile gloves are sturdy and they're safe for people who are allergic to latex.