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