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