"...it makes not a particle of difference that it really happened.  What matters is whether or  not the reader will be able to believe, as he reads, that it really happened this way." 


William C. Knott,
The Craft of Fiction, Third Ed., pg. 9.

Many people hear the words "Writing True Stories" and think this means
they can forget everything they've learned about writing stories!

They think that since they are writing a true story, all they have to do is to write down whatever happened--what could be easier?  In actual practice, it will be harder to write a true story than a fictional one. 

The story still needs a plot.   
XX Remember what the plot needs?  It needs a character with a serious problem.  This basically means you can forget the-night-we-had-so-much-fun stories.  There's usually no serious problem for the main character to overcome: it's just a bunch of guys running around having fun. 
XX When writing a true story, some writers also are tempted to throw in every detail because "it really happened."  In truth however, the writer has already omitted many details that "really happened" - for example, what they had for breakfast and what they were wearing.   The writer has to make decisions about what to include and what to exclude based what the plot needs and what the plot doesn't need. 

Coincidences
Weird things happen every day.  Yet, in books and movies, few of a character's problems are solved by coincidence.  Readers and audiences are seldom satisfied with a story in which the hero doesn't have to solve his or her own problems.  Sometimes real life problems are solved by coincidence, but in stories, it's pretty poor stuff.  If the story you have in mind depends upon a coincidence, write about something else. 

The story still needs a main character.
XX Because the writer of a true story may know the main character, the writer often completely forgets to describe the character to the reader.  A character's actions must seem reasonable to the reader, so the writer must explain enough of the character's motivation to do that.