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