In our local leagues, where I have had to keep time on field (once every other year), I do it this way, in games with 12 minute quarters:
- Quick notification after first play ends under 9 minutes, verbalizing "9 minutes left"
- Quick notification after first play ends under 9 minutes, verbalizing "6 minutes left"
- Quick notification after first play ends under 9 minutes, verbalizing "3 minutes left"
- Quick notification after first play ends under 9 minutes, verbalizing "2 minutes left"
- Quick notification after first play ends under 9 minutes, verbalizing "1 minutes left"
- Quick notification after first play ends under 9 minutes, verbalizing "30 seconds left"