I first learned this technique in a class I took with Lyla Messinger (L.J. Designs) many years ago. Lyla has a wonderful book called Ordinary to Extraordinary that details this technique along with many other fun and easy ideas to add uniqueness to your garments.
I've used this technique on several garments. It is most effective when you use fleece that has two different face textures. You can often find fleece with one smooth and one nubby side. Then it's as simple as cutting shapes from the fleece and appliqueing them onto the garment.
My first attempt was a vest which I made from a blue double-faced fleece. The designs also come from Lyla Messinger; she sells a pattern with several geometric shapes that can be used as appliques. I added binding along the center front, neckline, hem and armholes with the contrast side of the fleece showing.
Next I made a jacket from a red heathered piece of fleece and appliqued leaf designs on the back, front and one sleeve. The design for this jacket was based on an OOP pattern by Nancy Zieman. I found the commercial pattern too large for me so I re-drafted it using my Pattern Master Boutique software to better fit my frame. I made the button loop using one of my favorite notions, a FasTurn tube maker. I love this jacket and still wear it. I have fond memories about the time I made this. I was at one of my first sewing retreats with the Richmond ASG Chapter in Appamattox, VA (where I first met my sewing buddy, Jane). I finished this project (with lots of help from the other ladies there) but had no buttons that were appropriate. On my way home after the weekend I stopped in Charlottesville and found the perfect buttons at Les Fabriques. Good times!
More recently I revisited this technique when making some winter hats for my two boys. I started with a Kwik Sew pattern and cut the main pieces from fleece. I then cut lots of various sized circles and appliqued them on with the contrasting side showing. I used invisible thread on the top and an all-purpose thread in the bobbin (one of my sons is especially particular about "pokey" things which the invisible thread can occasionally be). I used a zig zag stitch and an open-toed embroidery foot. Once the main part of the hat was appliqued I finished the construction. I was hoping to post a picture of these hats in use but haven't been able to slow my two boys down enough to snap a picture yet.
Try this technique on your next fleece project. I think you'll like the subtle, tone-on-tone quality of this detail.