I wrote an step by step guide to docking your boat properly using a spring line with Dock Line Magazine.
“Master advanced boat docking skills with boating instructor Ned Files of High Tide Boating.
This step-by-step guide is an introduction to using a spring line when docking stern-to in a marina pen and is one of many advanced docking techniques taught by High Tide Boating. The boat used* is a twin-propeller,
shaft-driven vessel not fitted with bow or stern thrusters, though there’s ample manoeuvring capability with this twin-screw configuration.”