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