In order to sled correctly, a hill is much needed. It is possible to slide down a hill on a sled when there is no snow, but it can be a bit more difficult. I think sledding is also more enjoyable on a snowy day, and it makes sliding a lot more fun and easier. Sledding is also possible on flat grounds in the snow, but in order to move, you would have to get a running start with the sled in your arms, then falling to the ground with it after running. But when it comes down to it, I would suggest using a snowy hill to sled down.