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