If you want to keep your up and over garage door in good condition and make it last for a very long time, it would be a good idea to carry out a few simple tasks once a year.
Step 1 - Clean the outside of the garage door with a soft cloth and soapy water. Step 2 - Inspect the tracks and clear any debris from the tracks so that the roller wheels can run freely up and down the tracks. Step 3 - Lubricate the roller spindles in the tracks with a silicone based spray. Step 4 - Check the cables and springs for any wear and tear.
The finish of the door is designed to last a very long time and keeping the door clean on the outside of the door will make it last longer. If you wish to paint your garage door, find a specific paint that's designed to be applied on garage doors such as Hammerite garage door paint.
If you prefer you can always arrange a garage door service once a year with a reputable company.