Also, make sure your glassware is good for lacing. If you've put the glasses in the dishwasher, it could have soap or that "Jet dri" residue on it that will positively kill head retention.
An easy way to check that is to just moisten a glass and sprinkle inside with table salt. Using your hand, "scrub" the glass and over the rim with that salt. Then rinse well. And pour a beer in it.