Could you please explain how and where the tieback is attached so that the wall is not seen on this window treatment?
You would have to use a holdback that has an extended arm. There are a lot of them on the market now, they have a U shape. Italian stringing could also be done. If it is a short curtain, you may want to do a string measurement on the leading edge. This edge may need to be longer in order to have enough to tie back properly.