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