One way to learn Spanish fast, in addition to using a Spanish Course like Rocket Spanish, is to master vocabulary quickly and effectively.

Don't Over Do It

Now, you are reading this because you want to learn Spanish fast. Why exactly do you need to do this? Maybe you really don't want to learn Spanish but you have to pass some test for whatever reason. If this is the case, I would determine what criteria you are going to be judged by and then use that to guide your studies. Don't start learning how to say 'hello' when you are only going to be tested on how to count. The Two Main Ways to Learn Spanish Fast According to my experience, language learning occurs in two stages. Stage one is building the basics and stage two is building vocabulary and expressions. If you don't know a lick of Spanish, you are not going to pick it up with any rapidity without taking class of some sort. I would enroll in a class at a local university or community college. Another option is to take an online class. Stay away from the 'learn Spanish free online' stuff. Unless you are a language genius, you will not be able to get the basics without some form of formal instruction.

If you aren't able to find a beginners course that suits you, the next best thing would be to hire a tutor. Put an ad in the local newspaper or on Craigslist. You need a teacher to help you get the basics down before you can go out on your own. Taking a class or hiring a tutor is not enough. You have to continually consolidate everything you learn until it's imprinted on your brain. Everyone learns differently. For me, it's enough to repeat continually a certain phrase or vocabulary until it becomes second nature. This is sometimes excruciatingly painful as language drills are the stuff that can put insomniacs to sleep in minutes. However, your motivation or whatever deadline is looming in front of you may be enough to tread through the boringness of drills.

Vocabulary

If you need to know how to learn Spanish fast because you have a vocabulary test, well.. you couldn't be more lucky. This isn't language learning. It's just memorization. It could be Chinese or Sanskrit and it would still be easy. You are just memorizing one word for another. You don't need to know how to speak a work. Chinese students who want to study in America have mastered this technique. They have special classes that teach them how to pass the TOEFL test with needing to learn how to actually speak. I've met Chinese who have aced that test but couldn't speak a work of English with me.

Learn Spanish Overseas

If you have time and money, the best way to solve your problem is to learn to speak Spanish overseas. Try this search in Google to see the options that are available to you. I personally like the immersion programs in Costa Rica. They have programs for as short or as long as you can afford.

That you want to know how to learn Spanish fast doesn't really say enough about what you need. Why exactly do you need to learn it so fast? When you can answer this question clearly for yourself, the solution will open up before you.