If it's language of a profane nature, it's automatic.
If it's over the top in voice level and gesturing and it is clearly directed at the officials, it is automatic.
If they are on the court, it's automatic.
If they are outside the box and it is directed at the officials, it's automatic.
If they have already been given the stop sign, it is automatic.
If they are distracting you away from the game it is a warning. Mine has a visual stop sign and the words,"I've heard enough coach."
I never feel obligated to respond to statements, I have even used, "It's like Jeopardy coach, I need it in the form of a question." Use humor with care.
Most coaches want to be heard. Work on short phrases that quickly acknowledge their problem. Don't say anything you are not 100% sure of, and can back up if needed.
Keep in mind that those are my automatics and everyone's line will be different. That may sound like I am giving out T after T, but if you work on what I said in the preceding paragraph, those cases are very few and far between.