Step 1 The marquee tool can do more than just select a square (or ellipse). You can do a few tricks with it that make selecting odd shapes much easier.

Step 2 First, just make a selection.

Step 3 You may know that holding the shift key when there is no selection already on the screen creates a perfect square. However, if there is a selection on the screen already, the shift key adds to your selection whatever you mark. So, holding down the shift key, draw another selection.

Step 4 When you let go of the mouse button, the selection will automatically be added to your previous selection and look like this:

Step 5 You can also subtract from selections. You can do this by holding down the alt key while you make the selection. Do this now.

Step 6 When you let go of the button, this time whatever you selected will be subtracted from the original selection.

Step 7 Shift and alt buttons work with any of the selection tools (rectangle, ellipse, single row/column).

Step 8 Also there is one more trick that is very nice. Holding down the space bar while drawing a selection will allow you to move the entire selection. That way if you're trying to select something like a rectangle, and you miss by a few pixels, you don't have to start over with the selection, just hold down the space bar, and move the selection to where it needs to be moved.