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