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)(13,14,17,16)(15,19,20,18)(21,22)(23,25)(24,28)(26,27)(5,7)(6,10)(8,9)(11,12)(13,15)(14,18)(16,19)(17,20)(21,23,26,28)(22,24,27,25)(1,2)(3,4)(5,6)(7,12)(8,10)(9,11)(13,14,17,16)(15,18,20,19)(21,24,26,25)(22,23,27,28)(5,6)(7,10)(8,12)(9,11)(13,15)(14,18)(16,19)(17,20)(21,22)(23,24)(25,28)(26,27) involution — undirected(5,8,9,7)(6,10,11,12)(13,16,17,14)(15,18,20,19)(21,25,26,24)(22,23,27,28)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.