A putter shorter than 35 inches (the typical off-the-rack length) is better for most golfers. If your putter is too long, you'll have too much space between your body and elbows at address and your arms won't hang naturally. Telltale signs are scuffed putts, or the toe off the ground at address. Says Norton: "When we look at length, we're trying to get the player in a neutral setup, with the eyes over or slightly inside the ball. This allows the golfer to release the putter freely and see the line easier." Many fitters use a telescoping shaft to match length to the player's posture.
"You can have the right length, lie and loft, but if you're not aimed correctly, you won't hit it solid," Morton says. Many facilities check your aim with a laser device so you'll be able to see how different elements (circles, half-circles, lines) can help get you aimed at your target.
You need more loft on your putter -- at least 4 degrees -- if you play on slower greens or start your stroke with a forward press, which immediately delofts the putterface. You can get away with less loft on faster greens or if you contact the ball on the upstroke.
If your putts often come up short, you might be making off-center contact. A larger head with a perimeter-weighted frame that's more stable on off-center strikes will help. A blade putter looks more like your other clubs, so you might be more comfortable with it.
If the sole of your putter is not level with the ground at address, you'll leave putts short (because you're not contacting the sweet spot on the face). If the putter's toe is off the ground, even a perfect stroke will lead to a miss to the left.
Generally, a lighter putter -- under 340 grams -- works better on slower greens (because you need to swing the putterhead more), and a heavier putter provides stability on the shorter strokes used on faster greens.