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