Time Format:
8 a.m.
(never 8:00 a.m., use short version) *
9:30 p.m. (if half hour or quarter hour) *
Noon instead of 12:00 p.m. *
Midnight instead of 12:00 a.m. *

Examples:
8 a.m. to 10:30 p.m.
No colon after 8, leave space *
8 – 10 a.m. – no colon after 8, leave space, do not write “a.m.” or p.m. twice
Noon to 8 a.m. – leave space

* Special Notes:
– add the word “to” if it crosses from morning or evening to the other.
– Always leave a space after a number, like 8:00 a.m. not 8:00a.m.