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