Want to have an invoice copied twice on A4-sized paper

[SplendidDigital]

As part of offset printer's requirement for need of economy, want to have an invoice copied twice on A4-sized paper. Is there any quick method so that existing content replicates twice on A4-sized paper or rather what's the best way to do so? I mean I have prepared an invoice on Microsoft Word and now wants to have printed out 2 copies of invoice on an A4-sized paper to be submitted to my offset printer.