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