After takeoff, the slush could freeze the gear in the up position. After taxing in slush, leave the landing gear down for a minute after takeoff to blow as much of the slush as possible away before retracting the gear. Since wheel covers and fairings like to collect slush, it is best to remove them during winter. If there is fresh snow, the taxiway may be hard to see and the airport signs may not be readable. Don't cut corners too sharply, or you may end up in a hole along the edge of the taxiway covered by the snow.
Consideration needs to be given to the run-up.
Try to find a patch of pavement without ice, or else leave some space ahead to slide a little as you run up. In cold weather, when a lot of snow has been plowed, the snow banks can be high, and may be frozen. Watch the wingtips, and be especially aware of the position of the tail during turns. A frozen snow bank is hard enough to damage the aircraft. FAR 91.103 requires that we calculate required runway lengths for takeoff and landing.