I have a 3 way switch which gets its power from a ceiling light fixture by a 3 wire cable, white, red (hot) and black (hot) . This Switch S1 then is connected to a wall plug and then to the second 3 way switch S2 with a 3wire cable. All 3 way switch wiring diagrams that I have seen show power to the switch S1 by a 2 wire cable from the panel as opposed to a 3 wire cable from the ceiling light.
I would appreciate receiving either a wiring diagram or written instructions on how I should make the wire connections at the switches.
Thanks, Vals Husband

This Switch S1 then is connected to a wall plug and then to the second 3 way switch S2 with a 3wire cable.

Does that mean you have a 2-wire cable to the outlet and a 3-wire cable from the first switch to the second switch?