In the southern United States, most people grow warm-season grasses. These warm-season grasses typically go dormant in September when cooler air arrives and won't green up again until May. The most common of these warm-season grasses is Bermuda grass. In order to have a green lawn in winter, one must overseed one's yard with a cool-season grass, like perennial ryegrass. The perennial ryegrass has different mowing requirements than the Bermuda grass, but it is easy to mow winter ryegrass.
Check your lawn mower over. Check that the oil level is adequate and look for nicks and chips on the blade.
Set the lawn mower's cutting height between 1 1/2 and 2 1/2 inches. Taller is usually better for the lawn, but if you can't stand tall grass, 1 1/2 inches is still acceptable.
Cut your perennial ryegrass when it's dry. Don't cut it wet, because that can introduce disease and fungus into the grass. Also, wet grass cakes up the lawn mower.
Cut your grass in alternate directions. If you cut the grass in the same pattern each time, it will begin to lay in that direction. By alternating directions, the grass will stay upright and healthy-looking.
Cut your perennial ryegrass so that you don't remove more than one-third of the grass blade. The frequency of cutting can vary depending on the amount of rainfall and temperature during the winter, but generally one should expect to mow the lawn once a week.