People acting like this equals getting beat up. From my experience it doesn't at all, but people should understand the difference between escalation and standing up for yourself. Some people think they should escalate to show the bully what's up, that's a great way to force them into having to fight you.

Instead, I have always just been like "I am not fucking around, I will beat your ass, do something if you want it" simple as that I wouldn't go any further, simply state that I am willing and put the ball in the bullies court. It's worked for me many times. They typically follow it up with "whatever man". I have had it work on guys twice my size.

Another thing to keep in mind is gauging if this is a crazy people or someone trying to look cool. If they are crazy, then tell them to fuck off and walk away. If they are clearly trying to apply pressure to you to look cool in front of other people, odds are they aren't fully prepared to fight.