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