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