Select the faces or edges whose location you wish to specify.
Select a direction for the dimension.
Select Options > Create Ruler Dimension or right-click and select it from the mini-toolbar.The
start point of the dimension is set as the location of the
Pull arrow or Move
handle.
Click an object to set the end point of the dimension.Use the scroll
wheel if multiple objects appear at the same point in the Design
window.
Enter a value.
Press Enter to accept the value and complete the move
or pull.Press Esc to hide the ruler
dimension.You can make more than one change per ruler
dimension.
or press P.