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