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