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