First you have to get your head around the idea that there is really only one story. By that we mean this: every story you have ever seen or read is essentially an alternate situation superimposed, with individual style, over the same structure.
The Godfather (1972), Slumdog Millionaire (2008), Brokeback Mountain (2005), Gladiator (2000), Annie Hall (1977) and every other successful story you have ever seen or read are all one and the same - various situations superimposed over the same structure. Spielberg, Lucas, Scorsese, Coppola, Cameron all use this structure. Shakespeare used this structure. Stories in the Bible, the Vedas, the Torah and the Koran use this structure. You should use this structure.
Second you have to understand what is meant by structure. It is more than simple three or four acts or plot points etc..., it is a consistent, complex process through which your characters are led that results in them resolving their initial challenges. Many people are resistant to the idea that stories are processes because they are influenced by the many creativity myths.
Third, you have to understand, on a very deep level, what that structure is. It is the 510+ stages of the Hero's Journey you need to know about... and, on a macro level, involves:
...Movement through a number of Worlds.
...Transformation from various Devolved Selves to an Ultimate Self.
...Detachment from Older Worlds and Selves and Attachment to Newer Worlds and Selves.
...The Making Explicit of Deficiencies and the Gaining of Capacities.
...The Making Explicit of Challenges and the Laying Out of their Resolution.
...much, much more...
Fourth, you have to become adept with the structure, by superimposing various situations over it. The structure can be literal but it can also be highly metaphoric - it can take time to become flexible with the metaphors.
Fifth, once you have found a situation you are happy with, you develop your story by writing each sequence in your own, individual writing style. Once you have developed the competency, it is not necessarily that difficult: Sylvester Stallone wrote Rocky (1976) in three days, Joe Eszterhas wrote Basic Instinct (1992) in 13 days.
WRITE THAT SCREENPLAY!
The Complete 510+ stage Hero's Journey, Monomyth and other story structure templates can be found at http://www.clickok.co.uk/index4.html/
You will receive a free sample file by entering your email address at this site: http://www.clickok.co.uk/index4.html/