Easy cake!
You should find all the information on their website
Spanish is a must and if you are not a Spanish citizen you need to pass the ICAO language proficiency test in Spanish (is available only the level 4). You can get it in Spain, just search an ICAO certified centre writing on Google. If you speak Italian is a plus. During their conference in Rome, they declared the intention to hire up to 60 italian pilots. Anyway... 300 "factorized" hours are required.
As far as I know this mean, for instance, 1 hour on a non-airline twin engine must be multiplied by 0.5 and A320 hours by 0.8, is getting always worst for poor cadets!
Good luck.