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