Machine wash cold, delicate cycle. No chlorine bleach. Tumble dry low, remove promptly. Since cut edges of fleece fabrics do not ravel, inner edges of seams and hems can be left raw. When pinning pieces together, use long pins with bead heads.
Short pins tend to get lost.
Use a narrow zigzag stitch, adjusting width and length for the type of fleece you are using. It's a good idea to test first on some scraps. Sew slowly and carefully as stitches are hard to remove. When sewing around shaped areas, sew slowly, being careful not to stretch the fleece as you feed fabric through your machine. Machine Top-Stitch the edges and use this as a guide to keep stitches even .