Do you need Realignment?

Among the ways to check your alignment to see if canting might help you:

(1) The tiny-step test. Stand on an absolutely level,bump-free surface in a neutral stance, knees slightly bent, and walk in place, lift the feet only an inch off the ground, with each step keeping you soles perfectly flat and being careful not to let your upper body sway. The entire boot sole should contact the floor at the same instant - not one edge, then the other. If it's not perfect, you'll usually hear the double-click of one side and then the other of the boot sole hitting the floor.
(2) Apply packing tape to one side of the boot sole or the other, to lift that side up, or to the binding itself. To increase pressure on the side outside edge, build up the lateral side. Then test it on a firm, flat slope. You should be able to feel if the ski feels nice and flat, or is still biased toward one edge or the other.
(3) On a beginner hill with hard snow, ski straight down the fall-line. See if you can pivot you skis together back and forth a little bit without catching an edge. It may take a little practice. If it's really difficult, you've probably got a canting problem. You may find you have to move you skis far apart to do it, which means you're biased toward the outside edge. If you have to move you skis close together to get them pivoting smoothly back and forth, you've got too much inside edge. 

Ref-Ski Racing: Tim Hancock