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