One vertex per element, one color per generator, with an edge from x to x·s.
(1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31,32,33,34,35,36,37,38,39,40,41,42,43,44,45,46,47,48,49,50,51,52,53,54,55,56,57,58,59,60,61,62,63,64,65,66,67,68,69,70,71,72,73,74,75,76,77,78,79,80,81,82,83,84,85,86,87,88,89,90,91,92,93,94,95,96,97,98,99,100,101,102,103,104,105,106,107,108,109,110,111,112,113,114,115,116,117,118,119,120,121,122,123,124,125,126,127,128)(2,64)(3,127)(4,62)(5,125)(6,60)(7,123)(8,58)(9,121)(10,56)(11,119)(12,54)(13,117)(14,52)(15,115)(16,50)(17,113)(18,48)(19,111)(20,46)(21,109)(22,44)(23,107)(24,42)(25,105)(26,40)(27,103)(28,38)(29,101)(30,36)(31,99)(32,34)(33,97)(35,95)(37,93)(39,91)(41,89)(43,87)(45,85)(47,83)(49,81)(51,79)(53,77)(55,75)(57,73)(59,71)(61,69)(63,67)(66,128)(68,126)(70,124)(72,122)(74,120)(76,118)(78,116)(80,114)(82,112)(84,110)(86,108)(88,106)(90,104)(92,102)(94,100)(96,98) 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.