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