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