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