What type of paint should I use?

You can order Holi paint online. Alternatively, try non-toxic tempera powder paint. You can even make your own coloured powder: mix cornflour with half as much water and add food colouring. Use a blender to create a pourable paste, then leave to dry for a couple of days in baking trays. Preheat your oven to 180°C, turn it off and bake your paint with the door slightly open until dried out – 30 minutes or so should do the trick.