This is an easy way to attach wires without a permanent bond. It's also cheap!
Step 1: Proper Use
This procedure isn't all encompassing, so the first thing is to know where it is applicable. First, it is almost impossible to join two wires this way. Tape, crimping, and soldering are much more effective methods for that. This method will not work on contactless components or excessively large contacts.
Step 2: Kind of Tubing
I sue a simple black tubing found in the hardware store. Good tubes should be of narrow diameter, rubber and flexible. If the tube is metal, it ma conduct past the bond.
Step 3: The Process
First, cut tubing into little donuts, about the length of a contact. Second, place the rubber around the wire to be joined to the contact. Make sure the wire is stripped well. Finally, slide the ring onto the contact. The finished bond should hold tight, but could easily be disconnected.