When to Mow
Believe it or not, once-a-week mowing can do much harm to turf grass.  Rather, mow according to rainfall and temperatures.  The more rainfall and warm temperatures you have, the more you should mow.

Between early Spring and mid-June, mow your lawn when it reaches a height of 2-1/2 inches.  From mid-June through August, 3 inches is recommended.  After the first of September, reduce the height by 1/2 inch every two weeks until you are mowing at 1-1/2 inches as Winter approaches.

How to Mow
Never cut off more than 1/3 of the leaf surface at one time, unless you are renovating your lawn.  In addition, keep mower blades sharp.  Always mow when the lawn is dry and cut in a different direction each time you mow.