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