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