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