What do we need for spanish nationality?

am from england and as part of europe i think i would be able to get nationality of spain quite easy??? but my boyfriend is from venezuela latin america, in about 1 year we plan to move to spain as we want to have a family and a future there, but how hard would it be for him to get residence or nationality there? what is the best way to do it ?? mariage because am from europe? or first to get a job thenapply for nationality? thanks