You can start by opening your image. I like to duplicate the background so if I make a mistake I can easily undo what I did and if I make a big mistake or it doesn't look right I can delete that whole layer.
Then you can select your Spot Healing Blemish Tool.
Start by making the brush tool small around 20 px size. It is going to sample the area around the area you are trying to correct so make sure it is a small brush so it doesn't pull areas that do not match. Start by clicking on the areas of the photo you would like to correct.
Your results after should show you the difference between using the spot removal tool and the after affects.
Here is a video tutorial on how to use the Spot Healing Brush - Spot Healing Brush Video