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