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