A classic caipirinha is made with “cachaça” and if you are to buy one, I recommend getting a good quality bottle. Otherwise, you may use vodka (I actually prefer this version).
The trick to make it a good caipirinha (or caipiroska) is to use a full lime for each glass and lots of ice!
Cut the lime in half, squeeze the juice of one half into the glass. Cut the other half into slices and toss them in. Add ice so you fill at least half of the glass. If you don’t add enough ice, you may want to add a touch of water instead. Add 1-2 tablespoons of sugar (I personally prefer less sugar, when you add too much, people end up drinking faster than recommended).
Fill the other half with vodka or cachaça.
Stir and Enjoy!