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