I'm not doing Spanish, but I'm doing AS French. I'd recommend you do what you said - learn vocab, phrases and try practice questions. What I've personally found helpful is reading the news in French, reading books in French, listening to music, watching films and watching YouTube videos. As well as expanding my vocabulary, it's helped me get better at listening, because I agree, it is hard to work out what someone is saying when they speak fast (my teacher does this too). But honestly, if you listen to the language a lot, you'll begin to pick out more things that people say. Watching films etc also gives you much more motivation, because it's not as dry.