Cut the lime in half, put one half aside and chop the other half into small pieces.
Squeeze the other lime half into a tall or short 8 oz glass (see above) and add 2 teaspoons of white sugar, and stir vigorously until a lot (but not necessarily all) sugar is dissolved.
Add 8-10 mint leaves (no stems) and the rest of the lime and lightly muddle.
Pour in the white rum, add ice, fill with soda water, and stir.
Fill the glass with springs of mint.
You have an authentic Cuban mojito!
To give your mojito a Cambodian twist:
Crush one kaffir lime leaf lightly, add and stir, then add the second leaf as garnish.
Cut the lemongrass stalk to size so it resembles a straw, bash the root to release the aromas and flavours, and pop it into the glass.
Serve.