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To enter the stories UI click on 
at the top right navigation:
New stories can be created with 
. To edit an existing project, click on 
.
In either way, the Story Editor will open:
Upon start, you should make sure to choose the right size and margins, as a later change might corrupt the format. You can then start adding existing components by clicking on them. They will always appear on the top left of the selected site.
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