Add a dried rose petal to each empty ice cube space in your tray. Very gently and slowly pour fresh water into your tray. This works better if you're pouring the water using a measuring cup or spouted mug. If you try to fill it under the tap or your water filter the rose petals will just spill out.
Cover the tray and gently place it into the freezer. Leave the tray for a few hours to freeze.
When the cubes are fully frozen, use them in your mocktails, cocktails, or seltzers to add a gorgeous touch.