It didn't take long at all. First I made a quick triangle pattern, then cut out two of each fabric, sewed them together, flipped and pressed, arranged them in the order I wanted, then sewed a ribbon along the top.
I know it does look a little nurseryish, but that wall has been so boring for so long, and I really did want to make something fun for it. I had originally planned on hanging the banner across the window, but I don't know, I just didn't really want too. 
So, now it's up, making the horrid mint colored room a little more tolerable (I do have plans to re-paint it) and if it looks a little babyish, who cares, not me! 
If any of you want me to put the pattern up and make a tutorial just leave a comment, and if I have time, I would love too.
Yesterday I got the fabric to make this (unauthentic) medieval dress. I'm doing the view with the picked up hem. For the dress I got a dark brown suiting fabric (it was cheap) and for the underskirt I got a kinda pinkish almost taffeta like fabric for very cheep (it was only a dollar a yard!) at Joann's. 