I got a kick out of one reviewers comments about the L'Chaim Holiday Kitchen Blue Cosmo they said, "tasted like twenty packets of sugar dumped into a glass of Powerade" and a couple others didn't have flattering things to say about it either.
But to make one there are several recipes, looking at a few I think the one below would be a good place to start.
2 fl oz Ketel One Vodka
1 1/2 fl oz Cranberry juice drink (white)
3/4 fl oz Blue curaçao liqueur
1/4 fl oz Lime juice (freshly squeezed)
One thing I've learned is do not use the store bought lime juice. It will be much better with fresh. When it comes to Blue Curacao my first choice will be Senior & Co. Blue Curacao followed by Drillaud Blue Curacao. IMHO the one to avoid is the DeKuyper brand.