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