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