To make your snow paint, get a few plastic bottles with some kind of nozzle or small opening. Spray bottles, condiment bottles and sports water bottles with a push/pull cap will all work for this purpose. The spray bottle has a broader, lighter application, but it requires pump-action using the trigger. If youre dealing with a younger set and looking to occupy as much time as possible, that might be preferable. A more focused user might prefer the squeeze style application, which requires more control but gives broader coverage.
To make your paint, fill the bottles up with water and add several drops of food coloring to create the color you want. Unsweetened Kool-aid powder also works.
To make your colorful creation, head outside to the snow and squeeze or spray on your paint to create the desired design. More thoughtful artists might create simple scenes, shapes, hearts, words or color patterns. Younger, more impulsive artists might lean toward creating an environment that appears as if a unicorn fought in an epic battle.
Be advised that your paint may stain hands, clothes and outdoor surfaces, so use appropriate caution during your play.