OK, I will endorse two.
They cost a total of $1.27 combined.
Go to the hardware store and get a dowel rod. Put it outside the golf ball to display to you visually what the target line is. This will help you not whip it too far inside, not come too far from the inside…and not swing out too far. You have to do nothing but be aware of it and what it represents. You eyes and body will automatically adjust to the visual aid. It will also tell you if you are coming too far from the outside, as well.
DO NOT…I repeat do not tilt this to the right to create an inside/out swing path. I see this at the range every day and it creates a disastrous result every time I see it.
Remember, the golf ball it the outermost point of the swing. If you tilt this aid to the right (right handed golfer), you will create caca.
Go to the UPS store. Buy the smallest amount of bubble wrap you can find…or better yet, save some out of a Christmas gift you got in the mail.
Cut the grip off a club that you chip with. A backup that is in your old club bag. Fashion a grip out of the bubble wrap and attach it with two sided tape or epoxy. The bubble wrap grip will give you feed back on if you have too much grip pressure for your short game shots.
EDITED: Remember, you want a nice “medium” grip pressure. As most things are in golf, any extreme is bad. Death grip is bad and a grip pressure that is too light is also bad, because it is almost impossible to keep it fairly constant.
Also keeping it constant is another myth, but a well accepted term that refers to no wild swings in grip pressure.
The bubble wrap will give you feedback on all these issues and help you find the optimum level for you. The optimum level is different for everyone. What is universal. Death grip…bad. Holding like an injured bird….BAD!!!!
Somewhere in between and trial and error is how you find it.