Here's one of the earliest surviving episodes of The Tonight Show back when Johnny Carson hosted it. This is from 1/14/64 and by way of reference, Johnny's first episode was 10/1/62…so Mr. Carson hads been doing it for about fifteen months at this point. As you'll see, the show was looser and more casual than any talk show today — or even what Johnny did himself the last few decades he hosted.
The guest list includes "humorist" (that's how they usually described him) Sam Levenson, columnist Hedda Hopper, comedy writer Jack Douglas and Douglas's wife Reiko. Jack Douglas was one of the wittiest men in television back then though his spot here with Johnny was not his best. He and his spouse were frequent guests on the show when Jack Paar hosted it, though Paar — at least on a later talk show he did — spent most of those segments talking with Reiko. Paar got the rep for being erudite and witty but based on what I recall and clips I've seen, he liked nothing more than to have on people — women, especially — who were either dizzy or who didn't speak English well. He enjoyed making fun of how they talked.
Also in this episode: A rousing game of "Stump the Band." And it was even customary on The Tonight Show then to have the band play a complete number every evening. That tradition went away after a while as did the loose atmosphere…