As always there are some great suggestions here. I had a bunch of these coaxial cable nail-in cable clips (for RG6 I believe) so I use these for smaller wire bundles like track power drops. I leave them just a bit loose so I can add or remove wires as necessary.
I also use European style terminal blocks as the last termination before a wire goes through the layout (like for a track drop or for an accessory). This is so I can remove anything without cutting wires. I cut them down to typically 2 or 3 connections and place them within a few inches of where the wire goes through the layout.
Tony V
