Different types of subjects respond best to different types of sharpening.
In the Details panel, if you hold down the alt key while moving the sliders, you will get a better idea of what is going on.
100% zoom is good for seeing what the effect is having. 50% zoom is more representable with what the picture will actually look like.
It's not only the settings of the radius to get a picture sharpened. It's a combination of radius, details and masking settings.
There's a lot of tutorials of sharpening pictures.
And there are many more.
Thanks ManiacJoe and Axel. I already know all those techniques to sharpen but what I'm a bit surprised at is that usually moving the radius up to around 2 pixels works the best for my photos. This just seems to contradict what I've seen others saying including what Adobe recommended but then maybe my photos are different. The other general settings however, amount and detail, are more in the range of what others report for their liking.
Do you have an unsharpened example photo you can share with us, that is typical of what you shoot?
What camera to you use? Today's hi-res sensors need more sharpening in post processing than the older lower-res cameras.
I am assuming you are looking at your image at 1:1 in Develop. If you use any other viewing ratio, do not touch any of the settings in detail as you will not be able to see the actual impact of your edits. That said, the optimal radius setting really completely depends on the resolution of your sensor, whether it has an antialiasing filter or not, the quality of your lenses, and how good your technique is. If you have impeccable technique, superb lenses with resolving power higher than your sensor's resolution, and a sensor with no antialiasing filter, you might well find you have optimal results with sharpening below one pixel. If you have an extremely high resolution sensor but shoot handheld with good but not bank account breaking/outstanding lenses, you might well find you need settings over 1 pixel.