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