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