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)(13,14,18,21)(15,16,22,20)(17,23,19,24)(25,28,26,27)(6,10)(11,12)(13,15,18,22)(14,20,21,16)(17,26,19,25)(23,28,24,27)(1,2,3,4)(5,7,9,8)(6,11,10,12)(14,21)(15,25)(16,27)(17,19)(20,28)(22,26)(5,8,9,7)(6,12,10,11)(13,16,18,20)(14,22,21,15)(17,27,19,28)(23,25,24,26)(13,17)(14,23)(18,19)(21,24)(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.