How do you putt?

When setting up to putt...  I position the ball with the alignment mark in the direction I want the ball to go.  I then focus on keeping my stroke in line with with the mark.

I'm curious how everyone else lines up their putts.

I would seriously recommend you take a read of Dave Pelz "putting bible", it will change your out look on putting and will make a huge difference for your game.

A spot on the green before the hole I want the ball to roll over. I pick it, then don't think about it too much and focus more on the speed. I imagine a line from my ball to the hole the entire putt. I can usually hit my line I want ( whether I read the break right or wrong ), but speed is the key for me. I'm averaging 31.7 putts this season over 5 rounds, down from 34 total last year. Hopefully I can get it down to around 31 for the entire season. My putting has become a strong point of my game

i don't use any alignment marks on my ball when putting.  i visualize the line, pick a spot on the green in that line and give it a go.

I use a spot on the green and the alignment arrow.  I use the spot to control my distance and the alignment arrow to control my, um, alignment, lol.

i agree with most of the replies on how to set up for the putt

but i was wondering when youre about to swing, where are you focusing?

top of the ball?  behind the ball?  even in front of the ball?

I use the alignment arrows pointing to the spot on the green I am aiming for, usually a defect in the green or a color change that stands out... although something has to change, I've 2 putted every single green the last 3 times out, even with birdie chances from < 10 feet.

i go behind the hole and see the line...go behind the ball and see the line...stand behind my ball perpedicular to the hole and take 2-3 practice swings to gauge speed (ala Sergio Garcia) and then walk up to the ball...align putter...then stance...practice swing behind the ball...putter behind the ball...swing away.

Mine is a spot on my aimline, then i usually feel out the speed from there. I never pick a spot on my line, unless its a straight put. For example, i had a 25 foot putt yesterday that had 3.5 feet of break to it. The best spot i liked was the other golfer's ball mark. That spot was off my line but on my starting line. So my ball followed up towards that ball mark then broke, came up about 2 feet short, but it had a good line to it.

Yeah, i'm curious about that too... I was going to add that to the poll but I didn't want to complicate it.

I follow my putter with my eyes as it swings back.  That's probably a bad idea and i should probably have my "eye on the ball" but it seems to work.  I average 1.9 putts per hole.

Consistently badly.

I hesitate to say that I really focus on anything.  I sort of just allow my eyes to "see" a spot between my ball and the intermediate mark on the green that I used to line up my putt.  IME, I find that if I focus on something particular (ball, spot, whatever), I become fixated and I end up trying to steer my putter.  At that point, the results are usually a choppy stroke with poor contact,

I putt mostly on feel. I do try to get a read on the green and pick a a line that I think will be good. However thats just for setting my feet. Once Im behind the ball though I just feel it and hit it.