1. a viv or secure box, size depends on the size of the snake
4. 2 thermometers, one each end
5. water bowl big enough for the snake to get into
6. at least 2 hides (one for each end minimum)
7. substrate, again depends on the size of snake
save your viv money for when its a bit bigger, and get a food storage box from tescos and drill or melt some small holes in the side and top. for substrate use kitchen roll till its bigger, and for hides cut an empty bog roll in half and voila two hides. get the size of heatmat you will use when snakie goes into the bigger viv, but just put 1/3 of the tub on the mat. be sure to use a thermostat (matstat is good) to prevent overheating.
when snakie is big enough to go into a bigger viv keep the box for if you have to transport the snake, and also for feeding outside the viv if you choose to. also its somewhere secure for when cleaning the big viv
But - planning ahead - what you could do, so that you could use it with either a bulb or ceramic when you have a proper viv, is to get either a dimming or pulse stat now and use it for the heatmat in the meantime.
(If you got a dimming stat for a heat mat, it would have to be a Microclimate as they have a min load of only 5w - the Habistat dimming stats are min 40w.)
I agree with carl about dimming stats - except that the Habistat dimmer has a min load of 40w so can't really be used with single heat mats.
The Microclimate has a min load of only 5w so could be used for any wattage bulb and most, if not all, mats.