enclosure
i would buy one that will last, buy a 4x2 and just put a partition up, as he gets older you can remove the partition instead of having to upgrade from a smaller cage.
substrate
papertowels, butcherspaper, or non slip shelf liner (works really well) the shelf liner can be washed and reused, a great suggestion from mattman 
lighting
you will need a heat source (light and fixture), and a source of UVB (light and fixture)or you can buy a bulb that provides both such as a mercury vapor bulb. i also suggest you use an additional flourecent fixture and light just for brightness in the enclosure.
supplements
youll need a good multivitamin such as repcal herptivite and also a good calcium with D3 supplement such as repcal calcim with vit D3
cage furniture
something to climb and bask on, be it slate rocks or grapewood, babies love to climb and it makes them feel safe and secure.
feeders
youll need to find a cricket company and order in bulk if you are buying a baby, they eat a lot of crickets, my 4 month old goes through 500 on his own a week. youll also need housing for the crickets, rubbermaid bins and egg crates work very well for this. youll also need to feed the crickets wether you use a commercial type feed or feed the crickets the same veggies you feed your dragon.
fresh veggies and fruit
youll need to buy these weekly for your dragon even if he doesnt eat them at first they need to be offered every single day, salads become a very important part of the diet as adults.
back up funds
its always best to have some backup money just in case of an emergency, ya never know what is around the next bend. also its suggested that you get a fecal done when your new dragon moves in to rule out parasites from the get go.
find a vet
before you purchase your dragon, find a reputable herp vet in your area, always have that number handy and know where they are located.
hope i didnt miss anything, check out www.beautifuldragons.com lotsa good information there, any questions, just ask! 

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reiko 
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