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