
1: Make sure you properly cover the unit, at least the very top. This will help keep moisture and debris from getting inside and gumming up the works
2: Make sure your unit is level. An un-level unit can deteriorate over time and cause all sorts of issues, particularly with the fan.
3: Be sure to kee the area around your AC unit clear of debris and excessive vegetation. This gets your unit off to a good start once the weather warms up.
4: Think about having your AC unit serviced in the Fall instead of the Spring. They may catch issues that can be fixed now (instead of on the first 90 degree day of summer).