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