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