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