Many players release incorrectly because they can not physically produce the internal rotation of the hip needed in the downswing and release, use this quick half minute stretch before playing to work on your hip flexibility and allow your body to make the proper swing
An inside out swing approaches the ball on the downswing from too low, hitting the half of the ball closer to the player, causing a push or hook which requires the player to work on getting the club further up and out on the downswing
Learning how to judge the speed of a putt is a developed skill which can be improved with a simple drill like this one