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