Rule 6 3O enforcement - 20 second pitch rule

[wadeintothem]

What is the proper way to enforce 6 3 O?

Ive used the rule several times this year when the batters start the "take control time outs" (often I wont give it because I'm going to award them a ball if I dont get a pitch) and/or coaches are lagging with the signals. Usually call 1 or 2 and they get the hint.

But what is the most proper way to enforce it?

I've been declaring dead ball, ball on the batter. But the rule doesnt state the ball is dead and in the exam its not an illegal pitch. Its not really a DDB since you are stopping play.

Once I did say illegal pitch and learned my lesson, coach wanted his bases until I explained the "new rule" - but I stopped saying that.

Whats most proper way to enforce the time rule?