I just printed out a calendar for the new Year. I like to print out a LARGE calendar(44" x 26") that shows the entire year with lots of space to write on. Each month is printed on a letter size sheet of paper and then taped together. The calendar I print out is here from vertex42.com.
I add show deadlines, shipping deadlines, tax due dates (yuk!) etc. This works for me. How do you keep your deadlines organized?