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