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