after serging all open edges I sewed the side seam
then I did some stitching parallel to the seam
next I marked the hem allowance
then ironed the hem allowance up and folded in the centre front and centre back, then placed the flower on the side seam
glued it in place
and the sewed all around the open edges with small zigzag stitches
I hope this was helpful for you, if you have any questions, let me know!
keep sewing and smiling