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