Even though you may want to jump right in there and start using knitting patterns, making a knitting gauge swatch is definitely a good idea. You don’t want to skip this step, it’s not worth it. A single stitch in one inch can end up really making a big difference to the eventual size of an item from all knitting patterns.
It seems like a chore but you need just to learn that you will be thankful in the end. Always knit the swatch in the stitch that you will use. Obviously, different knitting patterns end up with different sizes so this matters.
I always try to make my swatch big enough to make it a good test. I usually go for at least 4″ x 4″. Surround the swatch with a few rows of seed stitch knitting (knit or purl the opposite stitch of what you see facing you on odd number rows). Begin and end each row with four seed stitches as well. This stitch lies very flat and will help you measure accurately.
Feel The Tension!
It may surprise you to know that the needle size is much less important than your particular tension with knitting patterns. Some people are loose with their knitting while others are tight. This can also vary from day to day with some people.
You can deliberately adapt your tension to create different looks from the same knitting patterns. Loose knitting for a light open feel and tighter knitting for a warmer feel. Remember also that you will get a softer feel from a loose knit and a stiffer feel from a tight knit.
When you have finished the swatch let it sit for awhile. The yarn needs to relax and even out any tight spots. Now count the stitches and measure the rows per inch of knitting. Remember to try a measurement in a few different places. Another way is just to calculate how big the total knitting pattern swatch should be.
If 16 stitches were cast on and the gauge in the knitting pattern is 4st=1″ then the swatch should measure 4″ The part you measure should not include the seed stitches.
Think about the size and adjust the needle size. For instance, if you are too small, try larger needles and vice versa. Now you have finished you can start using your knitting patterns with confidence knowing that the product of your labors will actually fit you!