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