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