For the best flavor, always use freshly squeezed lime juice. Bottled juice can have a metallic taste. Adjust the amount of simple syrup to your liking. If you prefer a tarter margarita, use slightly less. If you like it sweeter, add a bit more. Chilling the glass beforehand helps keep the margarita cold longer. For a smoky twist, consider using a reposado tequila that has been aged in oak barrels.