I personally find a good way to stop, Is by tapering off slowly. Just like with any addiction, stopping cold turkey, all but sets you up for relapse.
you could start by trying to harm somewhere that isn't quite as pleaseing, like moving from your arms to legs, or stomach.
then move onto doing something that doesn't draw blood, like a rubber band, or even your fists.
Ice cubes are good for wanting to burn. Hold an ice cube instead.
then you can move onto drawing on yourself, or something you find helps that causes no pain.
but a reward system is a good idea too.
While your doing all of this, you should find other coping skills, that help you, that aren't self harm related.
here's a little list of coping skills to get you started.- http://www.yourlifeyourvoice.org/sitepages/tips/tip-99-coping-skills.aspx -never be discurated by relapse, it happens to the best of us, and dosent mean you've failed.
I wish you the best in your mission.