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