I like to save any left over craft project, scrap fabrics, ribbons, spare buttons, laces, even the ribbon ties from shopping bags (like the hot pink one in VS paper bag). I know they will be very useful someday and can always be made into something, just like this hairpins project. Except for the metal pin which I bought for $1.5/pack (10 pcs), all the material here is from the saving box, the box where I put all the left over and spare things I mentions above.
They are all customized and almost free, what I need now is how to make my little one leave it alone, not trying to pull it off her hair. Hopefully it brings you inspiration!