The usual habit when making a sampler such as this is not to define Bargello Needlepoint edges. This makes the edges of one pattern flow into the edges of the others. The look can be subtle if the same colors are used throughout, as in my Bargello boxes, below. It can also be bold, as seen in Liz Morrow’s wonderful Bargello Sampler from Needlepoint Now.
But The Bargellist has come up with another choice. She defines the edge of each pattern with a line in narrow (over two threads) stitches in a different color, but following the same count. She also added some accents in this color as well. It makes for a lovely design.
She how she did it in two different pieces in this post.