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