You can type in an adress in the top left corner and/or via draging the map by mouse
Set the zoom level
to the approximate section of the region you plan to cover (action raidius of the Shared Walks Intervention) Therefore you can use the '+' & '-' navidation buttons on the bottom left corner or a mouse wheel.
Click at the center of the area
to set the marker.It is important not to forget clicking/tabbing there right before you continue with the next step, as the coordinates and scaling property will be stored by setting the marker.
Press the button "export map"
This one opens a new browser window which showes the selected map-area in full scale.
In the new browser window:
Open the print-dialogue-panel of your browser and you print or save the map as pdf for later print out.