The creeper's blocky geometric shape makes this a great beginner project for people unfamiliar with sewing. Also it's your best shot at giving a creeper a hug without it costing you the north wall of your house.
Step 1: That's a very nice EVERYTHING you have there...
Erasable Marker - you can find one made especially for fabric at any craft store
Fabric Shears - Aka big ol' pair of scissors
Green Fabric (fleece is good) - About half a yard should do, go to the fabric store if you don't feel like punching sheep and cooking cacti
Matching spool of thread
Fiberfill - Stuffing
Either black embroidery thread or black fabric scraps
Step 2: Anatomy Of A Creeper
Head: 4" X 4" X 4"
Body: 2" X 4" X 6"
Legs: 2" X 2" X 3" - Make four of these
Map out the panels for each side of these boxes on your fabric. Be sure to keep about a half inch allowance around the edges of each outline. Keep in mind that you do not need to cut out the top side of the body because it is closed off by the creeper's head.
When you cut the pieces out do not cut along the lines you drew. Instead, cut about a half-inch to a fourth-inch outside the line.
The pieces should be easy to recognize, but if you think you will have trouble mixing them up I suggest labeling each part, or cutting out only the pieces of the section you are working on.