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