I did a DIY on my car's gauge. not a civic though but its most likely the same for your car.
here are the things you need:
plastic polish, philips and flat screwdriver, microfiber towel, 6-8 peanut bulbs, lens brush (optional)

1. remove the screws holding the gauge bezel, check for other screws that need to be removed then pull out the bezel.
2. remove the screws holding the gauge, then pull out the harness.

3. with a flat screw driver, unhook the tabs holding the gauge's clear plastic lens.

4. apply plastic polish on both sides of the gauge's lens, let it dry then buff. repeat if necessary. clean the dials using a lens brush.

5. remove the old peanut bulbs and condom and place it on the new bulb.

6. reinstall the lens, harness, etc and enjoy having a neat looking gauge.