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