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