One vertex per element, one color per generator, with an edge from x to x·s.
(6,10)(7,14)(8,11)(13,18)(15,16)(17,20) involution — undirected(1,2)(3,4)(5,6,11,18,9,13,8,10)(7,12,14,20,16,19,15,17)(2,4)(5,7)(6,12)(8,15)(9,16)(10,17)(11,14)(13,19)(18,20) involution — undirected(1,2)(3,4)(6,13)(10,18)(12,19)(17,20) involution — undirected(2,4)(6,13)(10,18)(12,19)(17,20) involution — undirectedA 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.