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)(15,17)(16,21)(18,24)(19,22)(20,26)(23,27)(25,28)(1,2)(3,4)(6,10)(11,12)(13,15)(14,17)(16,25)(18,20)(19,23)(21,28)(22,27)(24,26) involution — undirected(13,16)(15,23)(17,26)(18,19)(21,24)(27,28) involution — undirected(2,4)(5,7,9,8)(6,11,10,12)(13,17)(14,20)(15,24)(16,26)(18,28)(19,27)(21,23)(22,25)(5,8,9,7)(6,11,10,12)(13,16,19,18)(14,21,22,24)(15,20,23,25)(17,26,27,28)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.