The following is a submission and artist thoughts & process from Robert Maitland. He was kind enough not only to provide several examples of his ambigrams, but also a thorough write-up accompanied by some visuals (hey we're artists & designers, so we need visuals!!) Here's Roberts' thoughts and process:
"Both Scott Kim and John Langdon have put forth much helpful advice on the ambigram creation process, so I feel that I don't have much new to add. But I will offer my personal process, for those who are interested. Generally I can figure out pretty quickly in my head if whether a word will work as an ambigram or not. Potential candidates get jotted down, and the boring and/or unreadable ones (usually about 60-70 percent) get rejected. (See figure 1)
Some words have multiple solutions ('strangers') and get branched out. Some can be stubborn ('double helix', which I still haven't figured out), at which point other types of symmetry are tried. The hardest part of making an ambigram is the finessing from a sketch to the final digital design. Because each ambigram is unique, there is no one method that is best. Most of my ambigrams are made from various circles and lines tweaked into what is required. It works well, but can be a bit boring if no flourishes are made. All editing is done using Paint Shop Pro 4. (See figure 2)
Some ambigrams are made from existing fonts, if the word is not too difficult. (See figure 3)
Hand-drawing is usually a last resort, if some particular curves are too difficult to achieve on computer. My drawing skills are unfortunately low, so I don't attempt it very often. (See figure 4)
Recently I have been experimenting with vector editing, which makes creating difficult curves much easier, although it does take much longer. (See figure 5)
One one tip that has helped me greatly is to study as many different typefaces and ambigrams as possible, to get an idea of what works as a letter (in terms of legibility) and what doesn't. Happy Ambigramming!.."
Robert, thank you for your great submissions and suggestions! (a link to Robert's page with more of his amazing ambigrams can be found under "Contributors" on the right hand side.)