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