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)(25,26,31,30)(27,35,38,32)(28,33,37,39)(29,40,36,34)(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)(26,32)(28,36)(29,37)(30,35)(31,38)(33,40)(34,39)(1,3,5,4)(2,6,7,8)(10,12)(16,18)(17,20)(23,24)(25,28,31,37)(26,33,30,39)(27,36,38,29)(32,40,35,34)(9,12,15,10)(11,18,14,16)(13,20,22,17)(19,24,21,23)(25,29,31,36)(26,34,30,40)(27,37,38,28)(32,39,35,33)(1,4,5,3)(2,6,7,8)(9,13,15,22)(10,17,12,20)(11,19,14,21)(16,23,18,24)(25,27)(26,35)(28,36)(29,37)(30,32)(31,38)(33,34)(39,40)(1,2)(3,6)(4,8)(5,7)(9,14,15,11)(10,18,12,16)(13,19,22,21)(17,23,20,24)(25,30,31,26)(27,35,38,32)(28,39,37,33)(29,40,36,34)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.