Swarovski DeLite crystals are this seasons new thing. They’re always extremely flashy - if you’re in a place with blacklight, they’ll light up to become even more sparkling!
You can easily attach them to a nail using Schtik it by Ugly Duckling.
Alternatively, use Gem Gel by Urban Nails.
With a Blinger it is easiest to pick up the crystals and place them right where you want them.