Monster Hunter 3 Ultimate for the 3DS before 11pm UK time on June 30 will be eligible for a recommendation code good for one download of Capcom's game. If your pal registers a Nintendo 3DS or 3DS XL through Club Nintendo between 11pm UK time tonight and 11pm UK time on July 31, and enters the recommendation code before 11pm UK time on August 5, then they'll be able to download the game.
So what if you already registered Monster Hunter 3 Ultimate 3DS? Check the Club Nintendo site tomorrow after 3pm UK time, at which point you should find your recommendation code available and can continue the rest of the process. The promotion only applies to the 3DS version – the Wii U game is not eligible – and Nintendo has announced no plans to extend the promotion outside of Europe.