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