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