Hello,
I will write the list for you.
You need a bigger tank. a 10 gallon is the smallest you can go and it will need a heat mat over to one side that doesn't cover more than 1/3 the tanks floor.
You will also need more than 1 hide. The leo needs a hide on the warm end, and the cool end. You should also add a "moist hide". We have instructions for how to make one on the site.
You need 3 dishes. A shallow dish to hold mealies, a shallow dish to hold water, and a shallow dish to hold the calcium.
I too suggest papertowels as a substrate right now. The leo is very thin and it will be easy to clean and monitor her.
I would suggest you grab a small container of waxworms when you grab the mealies. The waxies are high in fat and most picky eaters will eat them. Only offer 2 at a time, per feeding. The leo will likely eat more than its stomach can hold and will regugitate them.
I want to second that most petstores have no clue as to what they are saying. he sold you all that stuff because that is his job. If he thought you would have boiught it, he would have suggested a 55 gallon tank for the little guy as well. (Which isn't a bad thing, just expensive. lol)
You should also grab a digital thermometer with an external probe from walmart. That way you can monitor the temperatures accurately on both end of the enclosure. The radial ones at the petstore are junk.
I keep Leopard Geckos by the way and currently own 12 of the little buggers.