I use similar to these:http://www.ebay.co.uk/itm/2x-LONG-30-SOFT-FOAM-IRON-WIRE-TWIST-GRIP-Strong-Bendy-Secure-Cable-Tie-Bungee-/310410164756Orhttp://www.ebay.co.uk/itm/Industrial-Strength-Twist-Ties-2-Pack-Blue-High-Density-Foam-Coating-/230882486698The foam stops damage to the banisters.