How can I tune my Sony tv in to receiive a new dvd player?

I have a Sony trinitron tv/video combi 19"?(with video plus etc) but no handbook. I have just bought a Toshiba dvd player but need to know how to tune in the tv to suit. I have a three way scart switcher ie.one scart out the back of the tv converting to a 3 way.I have a digibox,Pace satellite box and the dvd connected to this. My brain is in a tangle as well as the wiring, can you help please?