K.C.
Get a sticker chart going and get him all excited about earning a sticker for being a "big boy" and have the prize at the end of about 2 weeks be something he would really want. Remind him when you tuck him in about getting up to go potty all by himself so that he can get the sticker in the morning and then make a big deal about putting the sticker on the chart the next morning. All you need is to get him focused on earning the prize and within a week, you should notice a big improvement. Oh yeah.. NO liquids after 6;30pm.