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