To make the simple syrup, mix the water with the sugar. Heat to boiling, stir until the sugar dissolves. Turn off the heat and toss in 10 mint leaves. Let steep for an hour or so. Strain out the leaves and store in the fridge until you are ready to use it.
To make one mojito: Pour 1 ounce mint-infused simple syrup into a tall glass.
Add 10 mint leaves, and muddle it together. (Use a muddler or a spoon.)
Add crushed ice. Muddle some more.
Add to that 1-1/2 to 2 ounces of light rum.
Squeeze in the juice of half a lime.
Add a splash of club soda and stir.
Garnish with a mint sprig and a slice of lime.
To make more, just remember the ratio: 2 parts syrup, 1 part lime, 3 parts rum. Oh, and lots of mint and club soda!