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