One vertex per element, one color per generator, with an edge from x to x·s.
(9,10,14,15)(11,12,17,16)(13,18,23,24)(19,20,21,22)(25,26)(27,34)(28,36)(29,31)(30,33)(32,37)(35,39)(38,40)(1,2)(3,7)(4,8)(5,6)(10,15)(11,17)(18,24)(19,21)(25,26)(27,34)(28,32)(29,31)(30,33)(35,40)(36,37)(38,39) involution — undirected(1,3)(2,4)(5,8)(6,7)(25,27,30,29)(26,31,33,34)(28,35,37,38)(32,39,36,40)(2,6)(4,7)(9,11,14,17)(10,16,15,12)(13,21,23,19)(18,20,24,22)(25,26)(27,31)(28,32)(29,34)(30,33)(35,39)(36,37)(38,40)(1,3)(2,7)(4,6)(5,8)(9,12,14,16)(10,17,15,11)(13,22,23,20)(18,19,24,21)(25,28)(26,32)(27,35)(29,38)(30,37)(31,39)(33,36)(34,40)(1,4,5,7)(2,8,6,3)(9,13,14,23)(10,18,15,24)(11,19,17,21)(12,20,16,22)(25,29,30,27)(26,31,33,34)(28,35,37,38)(32,40,36,39)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.