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