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