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