stay warm - winter is coming.
Fleece is stretchy and tends to bunch up ripple and sag when you try to sew on it. A quick way to handle that is to out line the deign in thread before you embroider your design.
once you've done a nice outline --- do a tight zigzag also known as satin stitch.
Try to do a tight zigzag but not too tight your going to want to sew forward and back just like the chain under -this will help make nice even lines with out the fabric getting stuck or getting bunched up or catching causing huge knots.