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