A Floor Mascot is a cool thing to start early in the year and continue to revisit throughout the year. I think that an important part of the mascot it to make it something that the floor can own. If you have a floor theme, choosing a mascot that fits the theme is a great idea, otherwise, having residents vote on an animal or character to represent the floor is a great way to choose something that residents are already invested in. I purchased cheap stuffed animals that represent our mascots to help make it more "real" and I would highly recommend this because it allows you to do some more fun things with the mascot.
After choosing the mascot, figuring out how to incorporate it into the floor is important. For the past two years I have had "We Saw What You Did Wednesday" and "Terrific Tiger Tuesday". On the first Wednesday (or Tuesday for the tiger), I nominated someone who had done something awesome for the floor community or made a difference to someone else during the week. I gave them the mascot for the week, and on the following week, that person is then responsible for passing it along to someone else. I monitor the passing to ensure that it is getting around to most of the residents on the floor and not getting passed between the same group. I also posted a sheet each week which listed the recipient and why they were given the mascot for the week. These were quotes from the person who gave it to them. At the end of the week I took down the poster and gave it to the resident so that they would have something they could hold on to to remember the good things they've done on the floor.
We also encouraged residents to help decorate or "dress up" the animals. Ear rings, necklaces, ribbons, small accessories, etc. were added throughout the semester as residents took ownership of our mascots. We also made sure that the mascots were present at all of our floor meetings.