I've found that even pinning can give me wonky seams but since I've begun using Clover Clips, I'm more successful. I clip at each seam intersection. When I've sewn to the clip, I stab my seam ripper into the seam and slowly sew until at least one half of the seam is secure. As others have stated though, the more accurate my cutting, the more accurate my seams and the less I iron and the more I press the more accurate my seams.