Cleaning your gutters a couple of times a year is essential to their functioning properly. Without consistent and proper maintenance, it may get to the point where it's as if you have no gutter system at all. Clogs and piles of debris will cause the water to spill right over the side of your house: the very thing you are trying to prevent. Fortunately, cleaning your gutters is not a complicated prospect.
Cleaning Your Gutters
Using a ladder, get high enough that you can see down into the gutters. Avoid leaning the ladder on the gutters themselves; you could bend or break them. Bring a bucket (or a heavy-duty garbage bag) for the debris, a trowel for scraping the caked-on stuff, and a big spoon for leaves and twigs if you want. Of course, there is always the option of simply using your hands while wearing some latex gloves.
Perhaps the most important parts to clean and unclog are the downspouts. Remove any elbow joints to clear them out. If your downspout runs underground, you may want to call a plumber to check it out, especially if you are having drainage problems.
After you have cleaned the gutters and downspouts, you should simulate some rain. Bring a hose up with you and run water through all the gutters. This should loosen what dirt is left and also show you if water is flowing down and out of the downspouts. If it is not, you may want to stick the hose directly down the opening and try to get as much water pressure as you can to flush it out. Once you see the water flowing freely through the system, make sure it is being adequately directed away from the house. If not, consider adding more length to your downspout.
To reduce your need for maintenance, you can install gutter guards, which are like metal filters for debris. The holes in them allow water to pass through but not leaves or twigs. They can be very simply installed with some screws and metal snips.
Cleaning out your gutters doesn't take much thought or effort: just a little time. As long as you don't have a problem with ladders (and depending on the size of your house), this is a chore that you can easily knock out in part of an afternoon. It may seem monotonous, but the benefits to your home's foundation and interior are huge.