How to describe 陈省身's name Shiing-shen Chern, 陈省身 (1911--2004), is a famous geometer.  When taking about him with Chinese people who do not study math and have not heard of him, how can I best describe which characters 陈, 省, and 身 these are?

Yellowbridge has many two-word phrases with 省 and I guess 反省 would be relevant.  But I am not confident whether it would be a good way to explain it.   

I guess 身体的身 would work well for 身.  

Would 普通的陈 work to say it is the most common name Chen?  Would it sound polite?

I do not think I could draw any of these on my hand well enough for anyone to understand!
I suggest just explaining the origin:

曾子曰：「吾日三省吾身：為人謀而不忠乎？與朋友交而不信乎？傳不習乎？」——《論語·學而》
The philosopher Zeng said, &quot;I daily examine myself on three points: whether, in transacting business for others, I may have been not faithful; whether, in intercourse with friends, I may have been not sincere; whether I may have not mastered and practiced the instructions of my teacher.&quot;
——&quot;Xue Er&quot; in The Analects (Confucianism). Translated in English by James Legge.

So, you can say something like

陈是耳东陈，省身是「(吾日)三省吾身」的「省身」。

I think Chinese should at least know the idiom 三省吾身(sān xǐng wú shēn), if not, it's an opportunity to teach them :)
PS for pedants: yes, yes, I know 陈 is not composed of 耳 and 东: 耳 should be 阜/. However in common saying, people just say so and everyone can understand!