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