The Kit has pronounced the must have look for Summer 2013 is "a playful approach with duo toned lips."
The magazine highlighted two colour ranges in particular: purples and pastel pinks. The magazine says, "Master the fashion forward, more is more lip colour trend," and "If neon is a bit much, blend creamy pastels from the same colour family for a subtle rainbow effect."
Have fun with your lip colours!
I suggest the following:
Daniel Thompson Beauty Transforming Lipstick in Iced Violet, Precious Coral, or Pink Coral.