In the digital age hand illustration may seem antiquated yet the ability to spontaneously produce an sketch to convey intent to a client is always in demand. The examples shown here either fully or partially digital. Most examples are from my time working in the architecture profession.
Having first learned how to illustrate by hand and then learned digital skills has helped me develop a hybrid method of illustration. Using the best of both worlds allows one to accelerate and fine tune the finished product of hand illustration.
My first professional illustration was coloring an elevation drawing of a cell phone tower.