Top 5 tips for those who've overrefreshed themselves the night before.
1. Go sick. Failing which
2. Smile a lot, say very little.
3. Breathe in through the nose and out through a corner of the mouth, sideways, when dealing with all other humanoids
4. Stay as far back from people's noses as possible
5. Don't mix it up with security over a cuppa.
Cheers.