Everything you need to start diamond painting comes in the kit - the canvas with printed image, dotting stylus, wax, tray and dots. Some kids also include tweezers / correction tools and bags for storing dots.
There is a plethora of optional extras or upgrades available to dotters including light-up pens and wax pots. One of the biggest challenges diamond painters face is where to store the dots during a project. Some diamond painters bag up their dots before starting or sort them into storage trays like this travel case one or this open style one. I'm lazy and simply open a packet then sit in a tray until I need the colour again.
I had been using a multi-compartment tray from Bunnings but one issue I had was that the dividers don't go fully to the bottom of the container so if the bags spill the dots can slide under the divider and then end up in a confused mess. These craft storage drawers from Spotlight are popular for diamond painters, especially those who keep their dots for future projects, however it doesn't have to be costly For my current project I looked around the house for holders and here I'm using a Tim Tam tray and a Tupperware burger press.