One solution for a flickering light bulb is to bend the tab in the socket slightly upward to assure a better electrical contact. The fix takes only a minute.
With the power off, bend the tab in the bottom of the socket slightly upward with a screwdriver.
Do you have bulbs that burn out quickly, lights that flicker, or a light fixture that simply doesn't work even though there's power to it? Try this 60-second fix before you call an electrician.
Turn off the power to the fixture and use a non-contact voltage tester to make sure the power is off. Then reach into the bulb socket with a flat-blade screwdriver and gently pry up on the tab that's centered at the bottom to restore good contact with the bulb.