Location Markers can be created at any position in a session.
To create a location marker using the Location Marker ruler at the top of the Timeline right click anywhere on the ruler and select New location marker, to move the marker to the current Playhead location right click on the new marker and select Move Mark to Playhead
See the section on Getting To Know the Ranges & Marks List for how to create a Location Mark at the current playhead location using the Editor List.
To create a Location Marker at the current playhead location using the kekyboard press Enter on the numeric keypad.
To create a Location Marker at the current playhead location using pull down mens select the Transport pulldown menu then Markers then select Add Mark from Playhead.
To create a Location Marker at a specific location in the Timeline using the keyboard, set the playhead to the desired location and press Enter on the numeric keypad.
Alternatively, a location marker can be set to a specific location by using the Ranges & Marks tab, using either the Use PH button to move a mark to the current playhead location or the clock to set a specific location manually.