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