Like a high-powered machine, your electric guitar needs care and attention to respond to your commands. Following is a checklist to keep it accelerating on the straight-aways and hugging the curves. Print it out and put it on your refrigerator for quick reference.
Even solid-body guitars (if they are made from wood) need to be kept in the proper atmospheric conditions. Use a room humidifier in the winter if your home is hot and dry. If you can't, keep them in their cases, away from heaters and radiators, when not being played. Use soundhole humidifiers, which are available at any guitar shop, for archtops and flat tops. (See Keeping Your Acoustic Guitar Healthy)
Newer, high-tech tuners are completely sealed up and require no additional lubrication. Older or cheaper ones, however, have small holes in the covers for the gears. Every six months or so you should carefully drip a drop or two of light, household oil (like 3-In-One, available at the hardware store) in the holes. A good time to do this is when you are changing strings since you will want to turn the tuning keys several times after applying the oil to spread it over the gears inside. Wipe off any excess oil immediately. Don't use so much that it leaks out
No, not your next door neighbor, but the rectangular piece of plastic, bone, graphite, or brass that the strings pass over on their way to the tuners on the headstock. If you are sure your nut is graphite, skip this section and move on to the next. For the other materials apply a little white, liquid graphite (hardware store) to each slot. As in lubricating the tuners, do this when changing strings. Every few months should be sufficient unless you have a whammy bar and go wild with it. In that case, perform this procedure every time you change strings. Hint: If you are ever in a bind out on the gig and feel the need to grease your nut, ordinary pencil lead, applied from the point of the pencil by rubbing back and forth in the string slot, works dandy. Nut Sauce and Lubrikit are also great solutions to this issue.
How hard you play, especially how vigorously you bend and vibrato, determines how often your frets need attention. Eventually all frets wear down. Check under each string on the lower frets (or any other area of the neck where you tend to play a lot) by pulling it slightly to the side. If you are experiencing noticeable fret wear you will see small valleys or dimples under the strings. If you feel that your intonation at these frets is off or if you are getting buzzes not caused by too low action, you are probably in need of a grind-and-polish job. Most players do not need this more than every few years. Unless you're well-experienced, it's recommended that this only be done by a qualified repairperson. It involves literally grinding all the frets (not just the worn ones) down so that they are again the same height. If your frets are new and/or jumbo-sized to begin with, this job can be performed several times before the frets become too low and require replacement.
Control Knobs and Input Jack
Whenever your controls crackle and pop, squirt some electronic contact cleaner (Radio Shack) into the noisy pots and then twist them rapidly back and forth for a few seconds. If you can get to them easily by loosening the pickguard or taking off the back cover plate, push the plastic straw supplied with the spray can into one of the openings on the pot and give it a short blast. If you can't get to the pots this way, carefully pull the control knobs off your guitar and squirt a very small amount of cleaner down near the base of each shaft, wiping away any excess immediately. A quick shot directly into the input jack will keep it clean and minimize wear caused by pushing the cord in and out countless times over the years. Better, use the contact cleaner on pots and jacks once or twice a year and you'll head off any problems.