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