just to identify your needs:
hard or soft nails? soft for safety.
how bad do you want it to be glossy?
latex allergy?
budget build?
if budget is low, no latex allergy, and soft nails are better go for Red2's idea. get some foam from the walmart craft section under $10, cut triangles then slowly nip at them with scissors until they resemble nails. glue the nails to the gloves. lightly coat in latex while worn and blow dry on low heat. once dry, they should hold shape, then add some latex tinted with acrylic paint for colors. even cheaper, just lightly paint a light colored glove with acrylic. just ideas of course. you have lots of options. I'm doing plastic nails I sculped/molded, on gloves coated in a stretchy rubber.