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