Separate a photo subject from it’s background in Photoshop
1.Click on the Edit in Quick Mask Mode button.
2.Make sure the colors that you are using are black and white, then click on the Brush tool.
4. Using the brush, make the whole subject red. The quick mask tool uses that opaque color red as a default.
5. Then click on the Edit in Standard Mode button and you should see that it makes a selection. Go to the select menu and click on Inverse. (Select>Inverse) which will then select only what you painted red.
6. Go to the Layer menu and select Layer via Copy. (Layer>Layer via Copy).