I was asked specifically for just the written pattern to the fan wave border for a reader, I published it for you all to enjoy.
Start off your wave fan edging by attaching your yarn at a corner of your previously completed project and chaining 3.
You will then dc into the next 3 sts.
Turn your work. Insert hook into 3 ch from beginning ch3 and sl st.
Ch 1 and turn work again.
Now work 7 dc into the ch4 loop.
Now work 1 dc into next 4 sts.
Ch4, turn, sl st into post of previous 7dc/4ch fan.
To go round any corners, just work 2dc, ch1, 2dc into one stitch at the corner, then create your fan as usual.