One vertex per element, one color per generator, with an edge from x to x·s.
(2,4)(5,6)(7,11)(8,10)(9,12)(13,14,17,19)(15,20,18,16)(23,27)(25,28)(5,6,8,10)(7,9,12,11)(13,15,17,18)(14,16,19,20)(21,22,24,26)(23,25,27,28)(5,6)(7,11)(8,10)(9,12)(13,16,17,20)(14,18,19,15)(21,22)(23,25)(24,26)(27,28)(1,2)(3,4)(21,23,24,27)(22,25,26,28)(5,7)(6,9)(8,12)(10,11)(13,14)(15,16)(17,19)(18,20) 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.