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