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