When I was a new fire lieutenants the best piece of advice given to me was to “keep your head”.  What on earth does that mean?  It means you’re going to encounter situations in which you’re not sure what to do.  Keeping your head means understanding your role.  As a fire lieutenant your job is to bring a sense of calm to a chaotic situation.  If you panic, your crew will panic, the bystanders will panic, the next in company will panic, so on and so forth.  In some cases just making a decision is half the battle.  It doesn’t have to be a perfect decision.  The fact that you are doing something vs standing outside panicking, is going to go a long way.