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