I think the most important thing with time travel experiments is attention to detail. One must be aware of many things: sounds, colors, expressions, inflections, font types, and the methods of producing all of these things. Getting the slightest thing wrong can jarringly bring one back to the present moment. If you're going backwards producing anything by hand will get you there pretty quick, but one must still be mindful of when trends came in and out. Minimalism is also a very useful commodity, even in an era where minimalism was not in vogue because nothingness; total silence, a black void, these things belong to no time at all and are absolutely true, magical, and readily available methods of time travel.
In our specific situation we must know exactly when we are going and who we are there. I know that Creatures of Yes is a low budget educational show in the late 1970s with a small but dedicated staff, probably in Akron Ohio. These cameras became affordable around this time, so it would make sense that we'd use them, but we could never afford computer graphics or anything that flashy. Thus, our show in the late '70s is dated. Watching it back then, one might think, "Gee, this seems a bit old fashion". I believe this layer of detail - being dated even for it's own time, adds immensely to it's authenticity. In truth, how many shows of this sort were ever cutting edge? Perhaps these days (now that children have money), but back then?
Our patron Saint, David Walter McDermott, once said "the further back in time you want to go, the more money you must have". He's right. This is one reason why time travel isn't for everyone, it takes a good bit of dedication to move through time at all (even the normal way - but that comes more or less naturally to most). If I had more money the Creatures of Yes would be a decade further back, set in the mid '60s, but antiquated to the '50s. I'm reaching for that time now, but it still seems so far away. It's like there's some impenetrable barrier right at 1969.