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