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