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