If the finished quilt will measure 5" by 7", I make the piece 6" by 8". After it has been quilted, I mark the finished perimeter with a washable pen and zig zag along this marked line with invisible thread in both the needle and the bobbin. I use Superior's Mono-Poly and a stitch width and length of 1.5 on my Bernina. I then use a rotary cutter and trim the piece just along the outside edge of the zig zag stitches.
Now, starting about one inch from one of the corners, I place Perle Cotton #5 on top of the right edge of the piece so it is lying next to the needle (see picture above); I leave about 2 inches of the cotton extending out the back. With Sulky 40-weight rayon in the needle and a matching 50-weight polyester in the bobbin, I use a blanket stitch (No. 329 on my machine) with a width of 3.5 and a length of 2.0 and encase the cotton along the top edge of the perimeter of the quilt.When I turn the last corner, I overlap the two ends of cotton and encase them together until I reach the beginning of the stitching (see picture at right).
I like to match the rayon thread to the color of the Perle Cotton, but obviously the sky's the limit when it comes to color combinations. My thanks to Terry Grant for the inspiration -- I love the finished result.