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