Once the grass growth slows down, continue to mow your lawn each week like you normally would . Each week you'll be able to lower your cutting height a little bit so that you're always removing 1/4 - 1/3 of the grass blade. Do this until the lawn is about 2 - 2.5 inche tall and continue to mow at that height for as long as the grass is actively growing.
Continuing to mow your lawn so that it is short (but not scalped) over the winter, will help prevent snow mold come spring time.
Most mowers allow you to adjust the height of each wheel. If you raise the wheel, you lower the cutting deck and as a result, get a shorter cutting height. A lot of times, people don’t realize that you need to adjust the back wheels as well as the front wheels.
Note: If you're mulching leaves, it is helpful to make one pass with the front of the mower raised high and the back of the mower cutting shorter. For the second pass, after most of the leaves are chopped, you can lower the front of the mower to match the back.
If you spray a little lubricant (like this vegetable based Lubri Magic) on the wheel height adjustment levers, they’ll be easier to adjust.