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