Adam and Eve costumes are a favorite pair costume for Halloween or costume events. However, many females simply choose to go as Eve. This is wonderful! Eve was more important than Adam anyway.
There are Eve costumes available at the Halloween shops. You may like to go to one and see them. They typically have one of two models: a 'sexy' one and a more covered one. The 'sexy' one will usually reveal a lot of skin and may not be proper for all events.
If you cannot find the version you wish, or you see them very expensive, you may wish to make your own Eve costume. This is not very complicated. Start by deciding how 'sexy' you want to be with this outfit. If you wish to cover as much skin as possible, then you will have to buy a nude colored unitard to use inside the costume. This will give the look of nudity, without you giving very much away!
Next you will need to make the outfit. You can either make a dress, or, more usually, a set of a skirt/panties and a bra/top. I propose buying a bra and panties set to begin with. If you can get them in green, then that's best of all.
Next, look for and get a range of fake leaves and flowers. You will be sewing or sticking these onto the bra and panties. You may also wish to buy green or brown colored pieces of materials to use as a skirt to cover the panties.
After all of that, you should get accessories. Typically, the accessories necessary for Eve are a packed snake, and an apple. Get creative with these! Put the snake around your neck and place an apple patch on the outfit! Or, make up your own. Have fun!