Just bought a used yamaha receiver model RXv793 do not know how to hook it up.

First do not panic by seeing all sockets in the back side of the receiver.You can connect 5 speakers and one subwoofer on the speaker A switch and maybe a second pair of stereo speakers on the B switch.All the speaker sockets have red and black terminals, so do all speakers. Just get decent cables ( You can buy a whole connection Kit if you want ) and connect the corresponding outlets to you speakers.If you have a powered subwoofer connect the subwoofer input to a socket labeled Subwoofer pre out on the RXV. You will need a RCA to RCA cable for that Next you will need a coaxial or Optic fiber cable to connect a DVD player digitally. The back of the DVD player will have a socket marked coaxial out, and so does the RXV's backside. Just link them .
Turn on the system everything should work. If you are not getting DVD sound there is small button on the RXV front panel called Digital input -- set it to auto ( keep pressing the button and it will scroll through various modes). Also remember to switch on speaker A on the front panel.

Register and download the manual for free at retrevo.com

http://www.retrevo.com/support/Yamaha-RX-V793-Receivers-manual/id/320ag020/t/2/