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