I've tried the clock face method but didn't find it too effective for me. I would trust the distance and I would end up mentally trying to accelerate or decelerate my swing and it would be all over for me. One of my former instructors was standing 5' from me and said "throw me that golf ball underhanded." Then he said "throw it over there to your bag." I did. He said "your body knew just how hard to throw it without you thinking about it. You gotta trust your hands." I've since read that in several different golf books.
I try to take my thinking out of the short pitch shots. I take a couple of practice swings then I take the shot not worrying about how far to take the club back. The more I practice at it, the more I hit the target area.
At the range I try to pick spots (usually patches of grass) out on the range 20-80 yds and hit 2-3 pitches/chips to them then alternate to another spot. I think that has helped me a lot. I used to hit 40-50 balls to the same spot and never seemed to improve my wedge play. Alternating to different spots seems to really help me start getting the distances trained into my mind/body. Now I seldom worry about how far I need to take the club back. I just focus on the target, take a couple of practice swings, and let my hands/body/pivot do all the work. I can get really close to where I aim.
One of the biggest things that helped is learning to hit with "the pivot." It has helped me out quite a bit on consistency. I'm not yet a pivot expert but as I get better at pivoting and lagging, all of my golf shots get better and more importantly they get more consistent.
Another thing that helped me is something another instructor told me. Don't take a full swing with your wedges. Never go more than 3/4 swing and if you need more distance, go up a club. I carry a 60* wedge and 52* gap wedge. Anything over 70 or so yards I grab the gap wedge. I hit the gap about 100yds with a 3/4 swing. Anything over 110yds I go up to the pitching wedge. That's helped me out a lot too. I have a tendency to lunge or raise up or over-swing when I try to hit a full wedge. When I pull it off it's nice but when I don't I either dig a trench divot or blade it 30-50 yards further than I intended it to go.