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