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