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