Most of the photography blogs that I read have a thread about sensor cleaning. It's the bane of digital cameras. While computers and digital imaging have opened up an amazing new world of vision for us, it's also given photographers some new frustrations. I can't remember ever being so frustrated by dust on the lens or mirrors of my old Canon A1. The occasional inexpensive cleaning and tuneup at my local camera shop always took care of the problem. All my old Canons from the late 70s and early 80s are still working just fine, BTW.
With the cost of cleaning digital cameras through the local camera shops being about $100 the last time I checked, I quickly looked for another way to get my sensor clean. My Canon Mark II is too old to have an automatic cleaning system. The Visible Dust Arctic Butterfly dust brush, cleaning fluid, and swabs work well for me. Their web site has detailed instructions for how to use their products and what products to use for your particular model camera. They go with me every tine I travel. Usually a quick swab with the Arctic Butterfly brush gets the job done. Occasionally a wet cleaning is needed, but it's not needed often. One bottle of fluid has lasted me a year. It's still 2/3 full. The system isn't inexpensive, but we all have a lot of money invested in good quality equipment. It's around $300 for a full kit. Brushes are between $100 and $180. I'm sure that many good cleaning products exist. This is the one that works best for me. The web site is listed below.
Hope this helps.
Photo credits: Patricia L. Ballard.