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