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