Hi, my lo is 15 mo. I would like to train him to use a cup but don't know how to go about doing it. Please advise. Thank you.

use a plastic cup or those cartoon cup which he likes. add about 1-2 mouthful of water in it. Hold his hand to guide him on the movement of the cup to mouth. It takes some practice in the begining to perfect it.

Try to transit using sippy cup first after that normal cup

You can buy a training cup with handles.