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