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