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