I've been cleaning my own sensors for well over a decade. Visible Dust products are head and shoulders above others. Yes CPS will clean a sensor, but you are without your camera and shipping gets pretty expensive, because dust comes back on a regular basis.
Done carefully, there is virtually no chance of damaging your sensor. Visible Dust has plenty of video tutorials to walk you through it. A key is hold the swab vertically for a few minutes after you place a couple of drops of Sensor Clean on the leading edge of the swab, this allows the liquid to soak in, and evaporate a little. One pass down the sensor, rotate it 180 degrees and make another pass in the same direction. Look at the sensor with a Visible Dust sensor loupe, shoot the sky at f16, see if you got it all. If you did, great, if not repeat until you do.
Very little pressure is required/suggested. Once you get the hang of it, you'll wonder why you ever went through the time and trouble to send it off. I have four or five bodies at any given time. I had to learn to do this.