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