Photoshop - How to separate the subject from the background
Here is one method I use:
1. Click on the Edit in Quick Mask Mode button
2. Make sure the colors that you are using are black and white
3. Select the brush tool
4. Using the brush, paint the whole subject - the colour should be displayed as red by default
5. Click on the Edit in Standard Mode button and the painted section will become selected
6. Go to the select menu and click on Inverse. (Select>Inverse) to select the inverse of the selection
7. Go to the Layer menu and select Layer via Copy. (Layer>Layer via Copy).
You should now have a layer with just the subject in it.