write a screenplay

a few years ago i had an idea for a film and i made loads of little notes ranging from the characters to little set pieces including dialogue. never thought about it again until recently i found some of my notes and it has rekindled my interest in it all. Its in the same mould as the brit flicks/guy richie stuff but with less gangsters. well less than the usual amount. Wont go into too much detail – dont want my masterplan taking away from me!