I recently have been involved in a project to decorate some wool cloaks for friends. Another friend made the cloaks up in this lovely brown wool, and I decorated them with simple geometric embroidery, with the designs based on the recipients' heraldic devices.
The left side shows the first stage of embroidery - mid-green crochet cotton. The right side shows the darker green bar being added in stem stitch.
Although it doesn't show up well in the photo, there is a small stitch in light green added to the points of the triangles.
This one has a simple geometric design worked in crochet cotton (stem stitch).
Because the cloaks were unlined, I used bias binding to cover the back of the embroidery.