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