Often a crochet pattern doesn't suggest a gauge swatch. It may say instead 4 stitches and 4 rows = 1 inch. To make a swatch make about six inches of chain. Lay the piece flat on a table. Count how many stitches there are in one inch. This is your stitch gauge.
Next, count the number of rows in one inch. This is your row gauge. Row gauge becomes important, when complicated stitch patterns repeat after a number of rows. If the shaping must take place at a certain row and your row gauge is different from the pattern gauge, shaping won't be done at the proper time and your garment may not fit properly.
Usually, if your stitch gauge matches, the row gauge will be close enough for most purposes.
If your gauge is larger than the one described in the pattern, use a smaller hook try another swatch. If your swatch is smaller, then you'll need to increase your hook. As hooks vary between manufacturers, you may find that switching hook brand can help you to reach the right gauge.
-A swatch should be at least two inches square.
-Always make a square swatch – it's easier to make an accurate count.
-Try not to force your tension, but crochet just like you always do.
-If you naturally crochet tightly, use a size larger hook than recommended.
-If you naturally crochet loosely, use a size smaller hook than recommended.
-If your foundation chain is too tight or too loose, begin the pattern with another size hook.
-Always measure the swatch on a hard, flat surface.
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