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