Knit or Crochet Slippers from Squares
Article by KarensVariety.com

You can easily make a pair of slippers in any size using knit squares or crochet granny squares.
 

Measure the length of your foot. This measurement will match the measurement of your first square diagonally, corner to corner. This first square is the sole of the slipper and will be crocheted in sc, hdc or dc or knit in garter or stockinette stitch. Once it is the correct size, fasten off.

Two more smaller squares are made, each half the size of the large square. These are the instep squares for the toe and heel which give the sole a double thickness. They can be plain or fancy. If you wish plain, make these in the same stitch as you made the sole. If you wish a fancier stitch or more colourful stitch, you can make these a lacier knit stitch or a crocheted granny square.

The final square is also half the size of the large square. This is top of the foot. Make it in a pattern stitch or decorate with embroidery or appliques.

Sew the insteps in place on the sole.

Fold the sides up and sew the top square in place. Use a contrast colour or sew on the reverse side and turn. Add a pompom if you wish, or a button or ornament.