All of the above plus lots of patience and take your time!

I would measure the size of the block in the center (best size) Then mark along the border to make sure you get it aigned correctly. Stay stitching might stretch the edge since it is all bias. It can be done with careful measuring, lots of pinning Make sure both sides of your border is the same size as well as the ends. Check Eleanor Burns web site, she has a book using scalloped edges. You can also use the same measurement of the side block and a dinner plate to make a template/pattern for your scalloped edge. Measure twice, thrice etc before you cut. You might also onsider doing a facing for the edge rather than put on a binding.

I believe that there's been a couple tutorials on the scalloped edges, try the search button.

You attach the border the same way you do a straight one with measuring in the middle of the quilt and using that size border.
When you sew, put the bias on the bottom so your feed dogs will ease it in and not stretch it.

putting straight border was just discussed at open sew at LQS by shop owner. She said to lightly spray bias edge with water and it should shrink a little. Put on border as usual by measuring in center. Fold border and top in 1/2 and 1/4 and pin to sides. using lots of pins ease quilt top sides into border. Sew with top on bottom so feed dogs help ease in the excess bias fabric. She also said do not stay stitch since that may cause more stretch to bias. Good luck!