One vertex per element, one color per generator, with an edge from x to x·s.
(1,2,3,4)(13,14,18,19)(15,16,20,17)(1,2)(3,4)(5,6)(7,10)(8,11)(9,12) involution — undirected(5,7)(6,9)(8,12)(10,11)(14,19)(15,20) involution — undirected(13,15)(14,16)(17,19)(18,20) involution — undirected(5,7)(6,10)(8,12)(9,11)(13,16,18,17)(14,20,19,15)(5,6)(7,9)(8,11)(10,12)(13,17,18,16)(14,15,19,20)A Cayley diagram is a choice, not a fact about the group. Another drawing of this group — in a book, or on a different generating set — may look nothing like this one.