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