This Covers the basics adjustments and setting in the Clarify plugin.
This tutorial shows how to add clarity and contrast sharpening with minimal haloing.
Upsize and Sharpen
This video shows how to upsize your image and sharpen with the Clarify filter. Since this program builds multiple clarity and sharpening maps, it can produce sharpening with less artifacts and halos. Also, it has an adjustment to preserve the original image color to reduce color artifacts from sharpening.
This effect has become very popular over the last several years. There is a built in preset for this effect so it can be applied to you r images with minimal effort.