How to get on the computer white collar?

First, we use PS to open a picture of a white shirt with a white background.

Then switch the selection tool to the magic wand indicated by the arrow.

Adjust the tolerance to 1 and check the anti-aliasing and continuity.

Click the first main matting on the white background.

Right-click and select Reverse, and then click Create Mask as shown by the arrow, and we have completed the first matting.

After the initial matting, we need to repair some parts and generally check the extra white background.

Then fill the mask layer with black.

For extremely detailed parts, you need to use a brush to perform point by point. After repeated revisions and adjustments, soon, the picture with white background was buckled.