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