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