A two-color, three-piece stuffed cat with only straight lines:

A fat quarter of cotton fabric for a one-color version, or
Two fat eighths in coordinating colors for the two-color version.
(Not sure what a “fat quarter” is? There are three pieces. Each can be cut from a sheet of standard paper. That’s also how much fabric you need!)
Coordinating thread or embroidery floss.
Needle, straight pins, scissors.
Two pieces of paper for the pattern and a pencil or pen, and a ruler (I use a fancy quilting ruler, but you don’t have to.)

Body pattern shown over a 1 inch grid.

Draw out the body pattern on one piece of paper as shown above.
Here are exact directions on how to draw it:

In the middle of your paper draw a rectangle 7″ by 2.5″ for the cat’s body. On top of one end, draw a 3″ by 3″ square for the head. On top of the other end, draw a 1.5″ by 3″ rectangle for the tail. On the underside, draw two 1.5″ by 3″ legs, one at each end of the body.

You’ll cut two of these from your fabric. Allow as much seam allowance as you like on the outside of the pattern, I use 1/2″ but you may prefer 1/4″ or some other amount. Remember to flip your pattern before cutting the second one, so both sides of your cat will be right side out!

Underside pattern shown on a 1 inch grid

This is the pattern for the underside of the cat– the belly and the underside of the legs. Draw this out on your paper.
Exact directions for drawing out the underside:

Draw a 2″ by 7″ rectangle on your paper. Attach 4 legs coming off either end of the long sides of the rectangle to form a letter H, each leg 1.5″ by 3″.

Remember to leave a seam allowance outside the pattern! Cut one of these from your contrasting fabric (or the same fabric if you prefer a one-color cat).

My cat is assembled as follows: fold the seam allowances in, pin them, then put the pieces together (removing the pins on each piece and pinning all the layers together at that point) and sew the seams from the outside. I prefer this for two reasons– it prevents stuffing from leaking out, and it is sturdier. I also prefer the hand-stitched look.

The leg seams before I put the stuffing in.

The bottom half of the cat is made by seaming the underside to the legs of each body piece; the top of the cat is made by seaming the two body pieces together. THE EARS are a little different– sew up the front and back seam of the head, then instead of sewing across the top, pinch those two seams together and sew crossways from ear to ear. (Like an old-fashioned creamer packet, if anyone remembers those.)

Something I learned to do on this project: my beginning knots are terribly lumpy, but my end knots are always neat. So I cut thread twice as long as I could use, tied a slip knot in the middle, then started sewing one direction. I knotted it when I got to the end and then returned to the other half and sewed that thread until I got to the end. So all my sewing threads here have a neat small knot at either end, hidden in the seam.

I left the back end and about 1″ of the tail unsewn for inserting the stuffing, and then put it in a pecan-sized piece at a time. The legs are sized so that I can just get my fingers in to poke the stuffing down, but if your hands are bigger you might want to use a pencil or capped pen for that.

Finally, I sewed the end shut and tied a yarn bow around the neck to give the head some definition. You could attach or embroider eyes if you like that sort of thing, too.