A Clean Appliance is a Happy Appliance
There are so many different ways to help maintain your appliances with a few quick steps.
For your refrigerator take a warm wet rag (a little soap never hurt anyone) and wipe down the seal before things start to gunk up. It will help maintain the seal and avoid unneeded replacements. Another quick help is to keep the condenser clean. (This should be done around every 6 months or so) Make sure to remove all the dust and build up regularly (as a note, it is a good idea to disconnect the power to your fridge before doing this). This will not only help your refrigerator last longer, but will also help save energy. When it comes to your dryer a clean lint trap and vent pipe makes all the difference. Make it easier for it to function, not harder. If your microwave seems too dirty for anyone to use, consider boiling water in a microwave safe bowl and just a touch of vinegar (to avoid explosion you can add a toothpick - bubbles will form on the toothpick instead of building up and exploding). The steam will help make it easier to wipe down and will require a little less elbow grease. For your dishwasher, again make sure to clean the seal. Have hard water? Try cleaning the inside of your dishwasher with a little vinegar. Remember that hard water or even food can sometimes clog the spray holes, just remember to clean them out occasionally.
All of these are quick and easy tricks to help maintain your appliances, so don't be afraid to try a few or even all.