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