Bicycling Magazine provide a pretty solid maintenance checklist for those getting their fair-weather bike out of storage, whether because they didn’t ride this winter or because they rode a beater bike.
The League of American Bicyclists ABC QuickCheck, as taught in Bike Ed courses, is a good checklist to execute each and every time you take the bike out for a ride.
Taking good care of your ride makes for a more pleasant bicycling experience for you and for anyone you might choose as a riding companion.