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