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