Cut up your citrus into small pieces, then place them in muffin tin or ice tray.
Fill up each space half way with water, then freeze until solid. (If you fill it up all the way, your fruit will rise to the top.
Once frozen, fill each space with water all the way to the top, then freeze until solid.
Once frozen, place your tray on a cookie sheet filled with warm water to release the fruit ice cubes.
Place in glasses, fill with more water, and enjoy!