The Properties palette is used by many to modify properties of entities. Unfortunately  leaving the palette open all the time takes up an enormous amount of real estate on your screen. 

The simple shortcut to open and close the palette is CTRL+1.  This is a handy shortcut, but a nicer approach to the open and close method is to leave the palette open with the auto hide ability enacted.

To make any palette auto hide just click on the icon with two arrows pointing away from each other at the bottom of the palette header bar.  The icon will change to a single arrow if the auto hide is switched on.

Another method would be to right-click the palette header bar and select auto-hide from the list.