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