Calling an illegal screen

[doubleringer]

Here's what I have. I try to get my fist in the air, but admittedly I know I get sloppy with this at the college level and it works its way into my high school games. Then I do my punch (team control foul) mechanic in the direction we will be going, say "illegal screen" and point to where the ball will be inbounded. At the table I report the color, number and give the team control foul signal and report it as an illegal screen. If a coach asks about it, I'll sometimes tap my knee, or toss out a little elbow to show what the player did.