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)(11,21)(12,17)(13,18)(14,19)(15,20)(16,22)(23,24)(27,29)(32,34)(35,36)(39,40)(1,2)(3,6)(4,7)(5,8)(9,11,15,22)(10,16,20,21)(12,14,18,23)(13,19,17,24)(25,26)(27,34)(28,33)(29,32)(30,31)(35,40)(36,39)(37,38)(11,22)(14,23)(16,21)(19,24)(25,27,31,29)(26,32,30,34)(28,36,38,35)(33,40,37,39)(9,12)(10,17)(11,14)(13,20)(15,18)(16,24)(19,21)(22,23)(25,28,31,38)(26,33,30,37)(27,35,29,36)(32,39,34,40)(1,3,5,4)(2,6,8,7)(9,13,15,17)(10,18,20,12)(11,19,22,24)(14,16,23,21)(25,29,31,27)(26,32,30,34)(28,35,38,36)(33,40,37,39)(1,4,5,3)(2,7,8,6)(9,14)(10,19)(11,12)(13,16)(15,23)(17,21)(18,22)(20,24)(25,30,31,26)(27,32,29,34)(28,37,38,33)(35,39,36,40)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.