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