One vertex per element, one color per generator, with an edge from x to x·s.
(1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31,32,33,34,35,36,37,38,39,40,41,42,43,44,45,46,47,48,49,50,51,52,53,54,55,56,57,58,59,60,61,62,63,64,65,66,67,68,69,70,71,72,73,74,75,76,77,78,79,80,81,82,83,84,85,86,87,88,89,90,91,92,93,94,95,96,97,98,99,100,101,102,103,104,105,106,107,108,109,110,111,112,113,114,115,116,117,118,119,120,121,122,123,124,125,126,127,128,129,130,131,132,133,134,135,136,137,138,139,140,141,142,143,144,145,146,147,148,149,150,151,152,153,154,155,156,157,158,159,160,161,162,163,164,165,166,167,168,169,170,171,172,173,174,175,176,177,178,179,180,181,182,183,184,185,186,187,188,189,190,191,192,193,194,195,196,197,198,199,200,201,202,203,204,205,206,207,208,209,210,211,212,213,214,215,216,217,218,219,220,221,222,223,224,225,226,227,228,229,230,231,232,233,234,235,236,237,238,239,240,241,242,243,244,245,246,247,248,249,250,251,252,253,254,255,256)(2,130)(4,132)(6,134)(8,136)(10,138)(12,140)(14,142)(16,144)(18,146)(20,148)(22,150)(24,152)(26,154)(28,156)(30,158)(32,160)(34,162)(36,164)(38,166)(40,168)(42,170)(44,172)(46,174)(48,176)(50,178)(52,180)(54,182)(56,184)(58,186)(60,188)(62,190)(64,192)(66,194)(68,196)(70,198)(72,200)(74,202)(76,204)(78,206)(80,208)(82,210)(84,212)(86,214)(88,216)(90,218)(92,220)(94,222)(96,224)(98,226)(100,228)(102,230)(104,232)(106,234)(108,236)(110,238)(112,240)(114,242)(116,244)(118,246)(120,248)(122,250)(124,252)(126,254)(128,256) 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.