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