[ From: firstname.lastname@example.org (Roger Christal) ]
Each player shoots 1 to 3 darts at the numbers 1 to 18 in order. The triple of each number scores 1, the double scores 2, the portion of the number between the triple and the bulls-eye (small single) scores 3, the fat portion between the triple and the double (large single) scores 4 and missing the number entirely scores 5. Lowest score wins. The player elects when to quit throwing at the number.
For example, if you throw a large single on the first dart, you can quit that hole with a score of 4. If you decide to throw again, the first dart is void. If you hit the small single on the second dart, you can quit the hole with a score of 3. If you decide to try for a better score with the third dart, the second dart is also void. If you have a bounce out on the third dart, your score is 5 for the hole. Got it?