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