My lens was clean for a change. I see only a couple dust specks on this picture. I am really bad about having dust on my lenses but am getting better at remembering to clean them.
Going outside and taking a picture of a clear sky is the best way to see if there is dust on your lens. If after cleaning your lens and you still see spots just like the one at about one o'clock above from the right end of the telephone pole crossbeam, then the dust speck is on your sensor. Do not touch the sensor. Read your manual on how to clean the sensor. If you look through your viewfinder and see a dust speck in the same spot with different lenses or no lens on the camera then the speck is on the Fresnel lens of your camera. That spot will not show up in your pictures but it is annoying to look at through the camera. You can easily brush or blow the dust off the Fresnel lens safely. The Fresnel lens is the frosted looking piece of glass inside the camera up underneath at the top.
Now if I want to remove a dust speck from a picture I use the clone tool in my photo program. You may be able to find about six spots removed in the picture below after cloning them out.
If you try to clone out a dust speck several times but it stubbornly remains, then the speck is on your computer screen. Um, that's another whole issue I really have got to get a handle on.