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