I ran into this problem a few years ago when I first became interested in working out. Buy a shaker bottle, and use more liquid than the whey container label says. They usually "6-10 oz" of water per serving, and a quick spoon stir is enough, but that's simply a joke. Add a serving of Whey, and 12 oz or so of milk, cap the shaker, and shake the hell out of it. 2 min later it should be clump free. If not, the whey product may be cheap quality.