Make sure you have read the tips:
100+ Hypermiling / ecodriving tips & tactics for better mpg - EcoModder.com
How many miles on the car? The first 1000 or so you won;t see the greatest numbers.
What are your driving conditions? All city, all highway, or a mix? I'm sure your car can whoop the heck out of the EPA numbers unless you have a terrible commute.
What rpm are you shifting at? Try shifting just before the shift light comes on, maybe sooner.
By the way the Veloster is one sexy beast.