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