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