How to do a Basic Wire Splice
I would add....use linerless electrical tape. Seems like it never fails that after you get everything hooked up that you find that you need to extend or shorten a wire or connect more wires to the same connector. If you use linerless tape you can easily remove it and you won't be left with all that sticky stuff all over the wires. I've always hated getting my hands/fingers covered with sticky goo when I remove old electrical tape. Then I found "linerless electrical tape". I'll never use anything else!! The linerless tape also keeps moisture out of the connection!!
Now when I work on old wiring I strip off all the old "sticky" cr@p", use electroclean to get all the sticky scum off the old wires then re-tape with linerless electrical tape.
My two cents......
treblig