Stitches on the needle are like upside down horseshoes. In English and Continental knitting, the open face of these horseshoes will slant to the left. After you've picked up stitches, pay attention to which way the stitches face. If one or more of them face to the right, it's the wrong direction. Either turn the stitches around so they face left, or simply knit into the back of them. The stitches you knit into the back of will then face to the left where they're supposed to be.
Mae West: When I'm good, I'm very good. When I'm bad, I'm even better. *from My Little Chickadee with WC Fields