Last year we had snack right after specials. The kids would get hand sanitizer as they were coming in the classroom and then get their snack that was set up on the back table. We would then have about 10 minutes to eat snack. I just allow them to socialize, but they have to stay at their seats and use inside voices, just like at a restaurant. We spent lots of time in the beginning of the year talking about expectations during snack time.
I send home a snack calendar on the last Friday of every month so that they have time to prepare if they have snack on Monday. I assign the dates in ABC order. It works out to about 1 time a month.
If someone forgets snack, we use leftovers or extras that the parents have sent in.
Our schedule is different this year, so I don't know how our snack time will flow this year, but I'll come back and post when we get started to let you all know!