Clean obvious obstructions such as newspaper, leaves, etc. from around the exterior of the unit.
Depressurize your home to help detect leaks. On a cool, very windy day, turn off the furnace. Shut all windows and doors. Turn on all fans that blow air outside, such as bathroom fans or stove vents. Then light an incense stick and pass it around the edges of common leak sites. Wherever the smoke is sucked out of or blown into the room, there's a draft.
Masking tape can serve as temporary pulls on new cabinet doors so you can open them without digging fingernails into a fresh finish. Make a tab and stick the other end over the door top onto the back. Tape can also be used as an edge protector for tool edges, or as a quick clamp for edge splinters that need to be glued down. It's also handy for marking locations for furniture hardware.