Is there certain things to look for when trying to pattern a buck in the snow? For example, rub routes, long dragging of the hooves, big beds?

In the snow during the rut, if you have snow, bucks will drag their hooves, so you can see that, they will also urinate on their hocks, so there will be urine stains in the snow as well.

**edit bucks drag their hooves all the time when they walk not just through the rut my bad**

Best thing about snow.

You can see what trails are being used very easily. Trails lead to food, deer need to eat, etc....

Find a well traveled route and stick with it, always keeping the wind direction in mind.

And it's a myth that bucks don't feed during the rut. They eat too.

Snow is great for hunting... If you have done your scouting homework in the past and know where the buck bedding areas are you can use fresh snow to determine if there are buck tracks going in, and not coming out... I do this from a distance so as not to spook the buck or let him catch my wind... For mature bucks I believe its necessary to hunt close to the bedding area and try new spots often to keep them from patterning you..
If you don't know where they are bedding, start at the food sources and follow buck tracks back till it starts looking like a good bedding area, then set up that day, before the buck comes thru and smells you were there.
Its relatively easy to hunt bucks in the fresh snow, but once the snow starts to melt and then freezes over night you get to the crunchy snow that is so noisy every animal knows where you are... I was able to put my buddy onto a nice 4 year old buck once in such conditions. I knew where he was bedding, but getting close enough without being herd was not possible. I tried getting in real early, but I would end up hearing him come out ( also crunching in the snow ) as I was leaving... Sooo, I took a friend in and he was to be the hunter. I walked him to the stand and he just climbed up and I never missed a beat and just walked by so the deer thought the passer by kept going. I did not even get to the car when my friend was already hollering that he shot the buck. He said it came out sneaky and was looking towards me when he shot it.