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