Let your tension square rest before you measure it. Or, if you’re feeling patient, wash it first – that way you’ll get a realistic view of what your garment will be like after washing.
Always make the tension square yourself, don’t use anyone else’s – everybody knits or crochets with a different tension.
Remember to knit or crochet the tension square using the recommended stitch. For example, if the pattern is in stocking stitch, knit the square in stocking stitch; if it’s in moss stitch, knit the square in moss stitch. If the pattern uses both stitches, knit two different squares.

