Choose your desired flavor for the slush, such as fruit juice, soda, or a flavored syrup.
Measure 500 ml of the chosen liquid and pour it into a shallow, freezer-safe container.
Place the container in the freezer for about 1 hour, or until the liquid starts to freeze around the edges.
Remove the container from the freezer and use a fork to scrape the ice crystals that have formed around the edges. Mix the ice crystals into the remaining liquid.
Return the container to the freezer and repeat the scraping process every 30 minutes for the next 2-3 hours, or until the entire mixture has turned into a slushy consistency.
Scoop the slush into serving glasses and serve immediately with a straw or spoon.