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