The key to making drinks is the balance between sweet and sour/bitter. Try not to let one element overpower the other.
Taste your drinks before you serve to make sure they’re wonderful.
If serving over ice, fill your glass to the top with the stuff.
Ensure your garnish is fresh and stacked close to the straws.
Remember that we drink in three steps, with our eyes first, then with our nose and finally with our mouth.