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