here are some you can use, hope you find them helpful :
- Smile (duh!)
- Use short and smart answers and avoid long boring ones.
- If they ask questions like "would you work in <holiday name here>" just say "yes" (companies seem to ask this question often to check if you're a hard worker or not , but careful cuz they might be serious )
- Use a joke or two in the interview ( unless the interviewer looks too serious or/and not in a mood to laugh ) , and don't be silly.
- look at his\her eyes while you're talking. This will make you look more confident.
good luck