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