If you own a DSLR, periodically cleaning your sensor isn't just good hygiene, it makes for cleaner, better photographs. Of course, getting the sensor properly cleaned can cost a pretty penny, but Blake Rudis of f64 Academy has this guide that will show you how to do it yourself -- the right way, of course. The video here is about 15 minutes long, so it's not a quick hit -- but it shouldn't be, if you want to make sure you cover your bases and do the job right. You'll need a few tools to do the job, though. They recommend a rocket blower, a sensor cleaning brush and a sensor cleaning swab kit -- but note the importance of getting the right brush and swab kit for your sensor size.
They also note that your best option is to avoid touching the sensor with anything if you can, so if you only have a little dust on it, start with the rocket blower and check after that to see if the air cleared up any noise in your photos as a result of dust. DIY Photography (linked below) also suggests that you avoid canned air, not just because it blows dust everywhere and can get it lodged into the corners of your sensor (as the video demonstrates), the article notes that canned air can leave a residue, or freeze moisture in the air, which can then settle on or damage your sensor.
From there, if you still see dust, you can move on to the brush, and then the swabs. (The video suggests this, but DIY Photography notes that the brush might just move dust around, when the swabs will actually pick it up, so go with your gut on that one. I'd probably still use the brush first, and then the swabs if that doesn't cut it to avoid too much direct contact if it's not necessary.) All in all, it's not too difficult to clean your own sensor, and to do the job right if you'd rather save some money and avoid taking it to a shop to have it cleaned. Hit play on the video above, or the links below to read more.