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