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