Suppose you are used to having the Clocks palette close to the bottom right corner of the screen. As the displayed times change, the palette will shrink and expand causing the gap to the right screen side to vary. Similarly, if you show and hide clocks or adjust the screen resolution, the distance from the bottom and right screen sides will change, requiring that you reposition the palette.
In general, if the Clocks palette is placed close to a screen corner or screen side, you may need to adjust its position from time to time. Anchoring it to a screen corner will save you this work, making sure the palette sticks where you placed it.
Start dragging the palette.
Press Command-A. The nearest screen corner will highlight in green (so you can always see which is the current anchor corner) and follow the palette as you drag it.
Note: It is important that you press the key combination after you have started dragging.
If you want to anchor the palette to a corner which isn't the nearest one, move the palette so that the corner highlights and press Command-L to lock the corner. The corner will turn red and stop moving as you drag the palette.
If you want to position the palette so that its horizontal and vertical distance from the anchor corner match, drag it towards the desired position and then move it slowly until a horizontal and a vertical guide appear.
Once the palette is in the desired position, release the mouse button.