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