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