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