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