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