Robin,

Here are a few I like to use:

make a number of putts from different places to the fringe, try and get the ball to stop as near the fringe as possible. It is good for distance but without the disappointment of not holeing the ball.

Place 4 balls equally spaced around the hole at a 1 foot radius, putt all 4 in succession, only when you have holed them all move them to a 2 foot radius, and so on wider and wider.