Not all digital photos have large areas of flat colors. Looking at the image of the backpacker above, you will realize that if you wanted to choose the background you will have to make several clicks and sometimes parts of the arm, or perhaps the face, might get selected. To remedy this, here are a couple of steps you can use:
1. Remove the "contiguous" option so that even those areas which are not physically joined are selected. Remember, however, that this tactic might not work if we are working on images which have small details, for example a picture of a flower.
2. To improve the ability of your wand to select colors, increase or decrease the tolerance setting depending on the area you want to select. For example, if you were working on a face of a woman, sometimes a single click might not work. Also, you will see several islands on the image and if these islands are not added to the selection, it could reduce the quality of the photograph. You can shift from default 32 to 50 and then use SHIFT+click to get a clean selection.
3. Use SHIFT+click to add areas to the selection and ALT+click to subtract from it. When you've already created a clean selection, you can now save it, so you can readily load them again in case you have to add new effects.
4. Sometimes, parts of the background will overlap. To remedy this, you can select the layer mask and apply a Gaussian blur using the smallest value you can use. You will also need to apply levels to the layer masks so that the blurred edges become brighter.