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I've never sewn anything before so this is a bit of an ambitious project, but I want to upcycle a dress for my graduation next month because I can't find anything I like that I can afford. I've figured out the shape I want (the pictures here are all held together with safety pins) and for the red skirt I'll just follow a tutorial, but I need some help figuring out what the next steps are for the top part.
I want the back to be open and I need to attach another piece of fabric to hold it together at the top (see picture with arrows), do I just sew lines where I've marked in red and call it a day or are there other steps i need to take? If anyone has patterns that might be helpful please let me know!