Smash mint with a spoon or with your fingers before or after adding it to the water to help it flavor the water.
Stir.
I find that letting it sit for a few hours really brings out the flavors.
If you plan to let it sit for a long time, remove rinds since they can add a bitter flavor to the water.
Fruit Ice
Using a small food processor, puree strawberries. Add water if needed so that the puree will easily pour into the ice tray. Pour into ice tray and freeze.