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