tough to say without know exactly what you are struggling with. 

pure stoke - get the cameron path trainer (or some tees) and work on your putter path

speed - use a ladder drill (3, 6, 9, 12, 15 feet) and look at the hole while you make your stroke.  Should get you back to "feeling" the stroke.

2 putts -  Take 2 balls and try to two putt your way around your entire practice green.  This brings in the pressure of making the putt when it counts.  if you 3 putt, start over.

Hope this helps...........

I might try that

" 2 putts -  Take 2 balls and try to two putt your way around your entire practice green.  This brings in the pressure of making the putt when it counts.  if you 3 putt, start over.  "

This is what I always try do do at the putting green but, the problem is : there are a lot of other golfers trying to practice putting and chipping as well. I rarely find the putting green open enough to actually start at one side and go around the entire putting green hole to hole and end up on the other side. Especially if I get there after 3pm when the high school kids show up. Nothing wron with them and, it's good to see them out there but 30 - 40 high school kids eats up the putting and driving range space real quick   :-(

I think we end up making putting too complicated with stroke mechanics and drills.  My putting improved when I focused only on reading the line and keeping a picture of that line in my mind as I addressed the ball and stroked the putt.  If you can get really focused on seeing the line and hitting the ball on that line you'll putt better. Also learn to see a wide path to the hole and try to hit the ball down the middle of that wide path.  It is easier to stroke a putt down the middle of a wide path than to hit it along a narrow path.  Hope this helps

I also like the "gate" drill.  If you don't have a trusty Cameron Path Tool, set your putter at address  and put a tee in the green on the toe side and the heel side.   This creates a little gate you have to swing the putter through to help repeat consistent contact.  I'd try it with 4 footers.  Be sure to stand on a towel to save the green from your footprints!

RC

I agree with RC on the gate concept in putting practice i also sugest a quality putting mat for the living room. perfered to be one with a line on it. it helps to build a smoth tempo with a consistant swing. you'll gain confidence in the inside 6 foot range.