To space controls equally:
Using the <Shift> key method (described in Selecting Controls), select three or more controls
Select Space Evenly from the Options menu
On the secondary menu, select one of the two options:
Space Evenly Horizontally reduces or increases the horizontal space between all the selected controls so that it is the same as that between the first and second selected controls:

after Horz space becomes:

Instead of using the menu you can simply press <Alt+←> after selecting the controls
Space Evenly Vertically reduces or increases the vertical space between all the selected controls so that it is the same as that between the first and second selected controls:

becomes

Instead of using the menu you can simply press <Alt+↑> after selecting the controls