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