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