Quick mask mode is a powerful way of selection in Photoshop. It is a selection based on the masking of the desired portion of an image. It is used for minute and accurate selections.
Start with opening an image with a multicolored background. Scenery will be the perfect example for background.

Figure 1: At the bottom of the Toolbox you will find the switches. Green marked button is for " Edit in Standard Mode" And red marked button is for "Edit in Quick Mask Mode"
Figure 2: Before starting with the tutorials, double click on quick mask mode. Select "Selected Areas" Keep the red color or you can change it. Default opacity is 50%. Make it 70 % if you want more dark color for selection. Click OK to close the dialog box.

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Figure 1: Select Magic Wand tool with 32 Tolerance. Click on the face of the image or click on the area you want to select. You can select maximum area by pressing Shift and clicking magic wand tool.
Figure 2: Click "quick Mask Mode". The portion of the image which was selected with magic wand will turn into red color with 70% opacity.

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Figure 1: Select paint brush with hard edge. The size of the brush depends upon the area you are going to paint or mask. For minute areas, the small sized brush is advisable. Keep black color as foreground and start painting the area you want to select.
If by mistake you painted something out of limit, turn white as foregoing and erase the red color with the same brush.
Use different size of brushes and zoom the image to paint minutely.
Figure 2: When you will finish with painting, click "Edit in Standard Mode" button. Red color will be replaced by normal selection.

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Figure 1: You can apply any filter or effect on the selected area or you can use it for retouching. In the following image we have desaturated the selected area with (Image > Adjust > Desaturate).
Figure 2: Or you can just drag the selection with move tool on another file to get the selection without background and place it on the new background.

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