Just to add another tip, I find that applying lip colour from the outer corner of the lip, sweeping inwards helps the lip to move gently with the brush/applicator, giving a more precise application (if you apply from the centre of the lip out toward the corners, the lips tend to pull against the brush and application is more messy). In addition, relax the lip muscles as opposed to holding them taut – this will also help to give a neat, mess-free application and prevent colour from bleeding.