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