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