An important part of camera & lens maintenance is to keep them clean. Earlier I went over the importance of keeping your digital SLR sensors dust free, and keeping your lenses fungus free. If you missed that post, you can see it HERE.
Today I'm going to offer a few tips for easy, at home cleaning. Below are a few cleaning tool options including a fabric lens cloth, a disposable lens cloth, & a lens brush. The last two items you probably already have in your home- an eraser and a Q-tip.
Sometimes the contacts on your camera and/or lens get dirty... you may not see anything, but it can cause connectivity problems so that your camera may not recognize your lens. An easy way to clear this up is to rub the contacts with an eraser. You can also do this on battery contacts, charger contacts, or anywhere else that you see those little metal spots. If you are rubbing contacts inside the lens mount of the camera, be very careful not to get any eraser crumbs inside the camera, they could get under the mirror and get stuck on your sensor which will cause spots on your images. You can also rub the contacts with a Q-tip that has some Windex on it. 
For cameras or grips that use AAA or AAA batteries, and has been stored for a length of time, it may have corroded batteries. In this case, an eraser or Windex may not do the trick. You can use regular white vinegar on a q-tip and rub it on the corroded areas. 
To clean your lens glass, a lens cloth works fine for minor marks like a finger smudge. For more intense jobs, first blow the glass element off (with canned air or a bulb blower) so that there is no harsh particles like sand or dust on it- it could scratch the glass during the next step if it's not first removed. Then, take a Q-tip with some windex on the tip and gently wipe the glass in a circular motion, and then dry it with the other dry end of the Q-tip. Windex may also be used on the camera body & the outside of the lens itself if there are scuffs or dirt, but prevention is also key! Smoking near your equipment and storing it in smoky places is a big no-no. The smoke gets in to all the little nooks and crannies and can not be removed. In addition to a smell, and possible internal damage, smoke leaves a yucky brown coating on equipment that is very hard to get off. For more preventative tips, you can refer to this post.
