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