You can't afford to get upset about a call and let it affect your focus. There have been times when I got so upset about an umpire's call that I caused our team to miss a scoring opportunity. Tell each baserunner the number of outs. Make runners aware of certain situations such as infield fly rule, what to do if the ball is hit to the left side of the infield, etc. It doesn't hurt to remind the baserunner whether or not he has to run when the ball is hit.
Most umpires just provide a hand signal.
This means that the runners advance at their own risk. The coach should already have made a decision about what to do if the Infield Fly is signaled. If it looks like a play could be made at home plate advise the runner to slide and tell them which side of the plate to slide to. All players should slide if there is any possiblity of a play on him. HOME - Windmill motion with left arm.