Purls stitches are larger than the knit stitches
 

My purl stitches are always larger than my knit stitches. What is the best way to get them the same size?

You most likely use diff tension when you P. Are you talking about rows of sts or ind sts? If rows, you can work the P rows using a smaller ndl. (ie K with a 7, P with a 6)

cam

You might want to try holding you yarn a different way. I may tighten both up but tighten the purls more.