And, well, mine are kind of on the heavy side anyway. The first day or two, I don't want to do ANYTHING. Make sure you keep away from me then.' I'd like to, but how can I tell?' I asked. O.K., I'll wear a hat for a couple of days after my period starts. A red one. That should work,' she said with a laugh. 'If you see me on the street and I'm wearing a red hat, don't talk to me, just run away.