Problems with composing the whole document in Scrivener

Hi all,
Beeing encouraged by positive remarks on the Scrivener app for iOS, I've decided to purchase it. I went through the tutorial and tried to figure it out. Although I have some questions and generally need some verbal step-by-step instructions:
I cannot prepare the whole document for export out of its pieces. To do this, I do the folloging
open the app create or select a project to open
write anything in the edit field and tap "done"
Then I select an option "add another document" and I skip the title and synopses but there is no separate editfield for the body text. Despite this, I write anything in the synopses and hit "done"
Then I do it again and again
and when I am finished I edit the project by putting pieces of text in the right order.
Then I select whatever I ant to have and tap "merge the document" and then I try to compill the text. After that only a short document pops out with its name and no words.
Please correct me and give me step by step hints how to use it or advice me anything better. I still have some days left to return my purchase.
Thanks for your patient assistance!