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