Illustrated (freehand) Portraits

I wanted to find a clean way to showcase two of my recent illustrated portraits. Technique; How it's done?

I am using Illustrator with Brush Tool and a mouse. Yes. All my lines are being done with zoom and mouse strokes. (a lot of patience). As for reference images, usually finding inspiration on Pinterest.

I have developed this art style by doing vector portraits and characters at first while experimenting with both Illustrator and Photoshop.