Here is a picture of the heels of a male and a female to show you the difference...
http://adcham.com/html/husbandry/glossary/tarsalspur.html
This site contains pictures of males and females...
http://www.chameleonjournals.com/icham/icham.php
Just a few things to be aware of....veiled females can lay eggs without being mated, so its important to have a suitable egglaying site in her cage. Failure to provide a suitable site could lead to eggbinding and eventual death.
Once a female is of breeding age, IMHO its wise to control her diet to decrease the size of the clutches so that she will live longer.
Veileds are omnivores, so I recommend that all plants in the cage be real and that they be non-toxic and well-washed (both sides of the leaves) since they (especially females) will eat them. They can be given an assortment of greens(dandelion greens, kale, collards, endive, ROMAINE lettuce, etc.), veggies (sweet red peppers, squash, zucchini, diced carrots, sweet potato, etc.) flowers (non-toxic) and fruits (apples, pears, melon, berries, etc.).
MBD is IMHO the most common health issue that veileds can suffer from, so I recommend that you use a full spectrum light (including UVB) or take her out in the sunshine (either should be direct, not through glass or plastic), dust insects with calcium on a schedule and gutload your insects well before giving them to your chameleon.
Hope she does well for you!