I clean my own sensor. It depends on what is on the sensor as to how to clean it. What I would strongly recommend is getting a sensor loupe, this allows you to see clearly what is causing the dust spot. If its just light dust I use Visible Dust Artic butterfly which generates a negative charge to attract the dust. If this won't work then I use a swab with approved cleaning fluid.
Having read several posts here and elsewhere about dirt on sensors there seems to be a myth that only by taking a camera to a specialist can it be cleaned. Totally untrue in my opinion. As long as research is done on how to clean a sensor, of which there are plenty of demos on youtube, it is quite easy and saves all that taking/sendaway/waiting time.
AS long as preperation is done first by getting the correct cleaning kit and have a clean environment such as a kitchen which generally is more dust free, then I would say have a go.
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