I would go a long with Robi. If you're sailing solo then chicken lines (restraining lines) are a complete waste of time as we only have one pair of hands. However, they are good if you sail two up but toe straps are probably the most convenient and safest option. If you do decide on chicken lines first cut the 4-5mm line to the desired length and fasten from the top rudder fitting on your transome to a hook which clips onto either your trap line or harness. Put a small pulley on this line prior to fixing one end. Then feed a bungee through you rear beam to the pulley and this will take up the slack in the chicken line whilst not in use. You will need end caps on your rear beams with hole drilled big enough to allow the pulley to pass through but not big enough to allow the hook from disappearing down the rear beam. In the attached photo of a tank you can make out the hook protruding from the rear beam but unfortunately you can't see the line tied off at the rudder pintle fitting.