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