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