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