That's pretty short notice, because you have to set up a habitat first. Could you possibly ask for a "gift certificate" or rain-check while your decide and create your first rainforest environment for it? You will need a lot more "stuff" than your first frog, well before you get it, such as fruit fly cultures that you can maintain, and lots of information that can't be condensed here. This is a hobby that takes quite a bit of pre-planning and homework, or you may be disappointed.
My favorite beginner frogs are D. leucomelas or P. terribilis. They are both bold and relatively easy to keep. Search for breeders and their care sheets, which most provide over the internet. Look at our own gallery of tanks and vivariums. It doesn't have to be very complicated, but it does have to be the right size for the frogs you will get, keep the proper temperatures and humidity. Most of us use live plants, so you need to know something about growing these in the vivarium and which ones will work, and what lighting to use for them. In other words, you need to "plant a garden first."
Welcome to the dart frog hobby, but take your time with it.
Maybe you could tell us what other reptiles or amphibians you keep and what set-ups you have for them and we could give better advice from there.
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Patty
Pahsimeroi, Idaho
4 D. auratus blue
5 D. galactonotus pumpkin orange splash back
5 D. imitator
6 D. leucomelas
4 D. pumilio Bastimentos
4 D. fantasticus
4 P. terribilis
4 D. reticulatus
4 D. castaneoticus