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