I will present a procedure that, given a Cayley graph of a finitely generated group, results in another finitely generated group with properties similar to some of the given group. This procedure is called "cubization", and relies only on elementary techniques concerning coverings of graphs. One particular feature of a group obtained by cubization is the lack of Kazhdan's property (T). I will present an application: a construction of free Burnside groups (that is torsion groups of bounded exponent) acting on CAT(0) cubical complexes without fixed points. In particular, such groups do not have Kazhdan's property (T). The talk will be fairly elementary - I will use only basic facts concerning Cayley graphs of groups and coverings of graph