[soylentcola]

Not an expert photographer, but while there are plenty of more "authentic" ways of reproducing the older photos, there are also lots of post-processing tools for digital (Photoshop plugins and the like) that do a great job of simulating all sorts of film stocks.

I've messed with these a bit: https://www.google.com/nikcollection/

They're a step above your typical Instagram-type filters and you can tweak effect parameters and strength depending what you're going for. It can easily devolve into gimmickry and I'm sure a skilled photographer and editor can do more without presets/plugins but for the average or hobbyist photographer I've found them to be a good starting point.