Spot healing brush
The spot healing brush removes small blemishes with a single click, without you having to set a source area. Photoshop automatically picks matching texture from the surroundings. It is the fastest way to clear up pimples, dust and small spots.
Grab the spot healing brush, set the size a bit larger than the blemish and simply click on it. With the Content-Aware option Photoshop fills in smartly based on the surroundings. Work on an empty layer with Sample All Layers, so your retouching stays non-destructive and reversible. Tip: for larger or awkwardly surrounded spots, choose the regular healing brush, so you set the source yourself.
Prefer a look in one click?
The presets on this site set these adjustments up for you as a starting point, which you then fine-tune to taste.