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