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