To write a story in AP style, you need to abide by the Associated Press handbook of rules for punctuation, capitalization and certain other details. There are some 5,000 rules in all, and they are frequently updated. A good grasp of the basics will ensure that your news story achieves the AP goals of consistency and clarity.
Use a period and a single space at the end of a sentence. Punctuation ending a quote goes inside the quotation marks. Don't use a serial comma before "and" when you're listing several items unless the last item has its own conjunction: "The mayor's office, the highway department and the parks department" is correct, as is "the mayor's office, the highway department, and the department of parks and recreation."
AP Style for Proper Nouns
The first time you identify a person by name, use his full name; for the rest of the story, use just his last name. Don't use courtesy titles, or use the first name again unless you are writing about more than one person with that last name; both John and Jane Doe, for example, or Joe and Jack Brown. Capitalize formal titles only when they're used right before a name: Mayor Joe Smith or Mayor Smith; the mayor said (not the Mayor said.) Capitalize brand names and names of corporations. Spell out an acronym the first time you use it; for example, if you are talking about the United Nations, say so the first time and then refer to it as the U.N.
AP Style for Dates and Times
Abbreviate long months; spell out March, April, May, June and July. Use numerals for the date (May 3, not May 3rd) and a comma between the day and year. If you're using just a month and year, spell out the month. For times, use numerals unless you are referring to noon or midnight. If a time is on the hour, don't use :00, just say 11 a.m.; if the time you're writing is 11:25, use a colon between hours and minutes. Don't capitalize a.m. and p.m., and use periods.
AP Style for Numbers
Spell out a number that begins a sentence and numbers smaller than 10, and use numerals for the rest. Use numerals when the number is someone or something's age; if the age is written as a noun, use hyphens (9-year-old.) Use numerals when writing percentages or dimensions, and spell out the words "percent," "inches" and "miles."
AP Style for Place Names
Use numerals for house numbers or for street numbers higher than nine, and abbreviate street, avenue or boulevard and directions when they're used as part of an address: 101 E. Lake Blvd. is correct, but if you refer to the street without an address, it's East Lake Boulevard. Spell out the names of states. AP has a list of 30 cities considered so well known that they can be referred to without an identifying state; check if you're not sure.
The Associated Press isn't just concerned with where to put your commas and what to capitalize. The organization abides by a set of values that cover a wide range of the situations journalists face on a regular basis. Whether to use anonymous sources, how to incorporate graphics and photos and what are considered conflicts of interest are just a few questions covered; many media outlets besides the AP consider these rules the generally accepted standard.