How to do A Quick Mask in Photoshop

Firstly choose the image that you want as the subject and I choose Basketball .

Second step click Elliptical Marquee Tool and click to the ball and drag follow the size of the ball

Third step click the quick mask tool which is under the color picker. After click it the red color will appear.

Lastly , we choose Brush tool or you can click Shift+B to brush the the part that haven't fulfill in the second step.

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