Custom Normals 2: "Cylinder" Face

Shading the face cylindrically is slightly more advanced but still a simple and lazy process.

Select your head/face mesh and open the right-side panel (press N). Under the Abnormal tab, there is a drop down selector that should show a list of your mesh's vertex groups. Select the "Custom Normals" vertex group we created earlier.

Start Abnormal with the "Start Normal Editor" button. Every vertex should already be selected, and you'll see long pink lines in every direction representing the directions of the normals.

Select "Sphereize Normals" and then "Confirm Sphereize" to apply. The normals of the face will appear spherical. Under "Flatten Normals on Axis", press just the Z button. "Confirm Changes" under the "Finish Modal" panel. The shading of the face now already appears cylindrical, but we should refine it further.

Select the "Custom Normals" vertex group you created and make a copy of it. In Weight Painting mode, enable "Paint Mask" and select everything again. Use the Weights -> Levels tool with a gain value of 0.5 to halve the influence of the copied vertex group.

Back in Object Mode, open the Abnormal panel again and use the drop down to select your copied Custom Normals group. Enter Abnormal and under "Flatten Normals on Axis", press the X button. With our copied vertex group, this only half-influences the selected normals, flattening them out on the X axis only a little bit.

The shading of the face now has the appearance of a larger cylinder with a larger surface.