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