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