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