You can freeze the unfrosted cupcakes up to three months ahead. Frost and decorate the frozen cupcakes, and let thaw at room temperature.
Bake the muffins in decorative paper baking cups found at party stores or cake-decorating supply stores.
If you have only one pan and a recipe calls for more cupcakes than your pan will make, cover and refrigerate the rest of the batter while baking the first batch. Cool the pan about 15 minutes, then bake the rest of the batter, adding 1 to 2 minutes to the bake time.