What are the best tips for getting fast and accurate at Doomsday?

Over-learn the anchors and doomsday dates, always count from the month's doomsday, and self-check with a known date.

• Automate the tables — century anchors and the 12 doomsday dates must be instant, or the method stalls.
• Count from the month's own doomsday date, so offsets stay under 7 (and can be negative).
• Sanity-check against a date you know (your own birthday) to catch a slip.
• Practise daily with random dates — speed is pure repetition, and sub-10-second times are a realistic goal.