Learning a language is essentially different from learning anything else like science or humanitarian subjects. All the other subjects are learned from research, logic, knowledge and practical experiments but languages are learned from observation, experience, surroundings and environment.
Some of you might differ with my statement, but think of it like this. When you start learning your first language, you are too young and innocent to scientifically explore anything. It is your observation and experience from surrounding environment that makes you learn your mother language. You would not know the grammar and rules of your mother language very well but you have an expert command over speaking, and sometimes, reading and writing as well. Take the foreign language learning the same way.
The quickest way to learn Spanish is to construct a Spanish environment around you which can give you maximum exposure to Spanish. You can do so by following the steps discussed in the following:
1. Take admission in some Spanish class or Spanish speaking group. Mostly it is available in schools and community colleges around you. This would provide you with people to speak with. You will hesitate less with them as they will be on your level.
2. Listen to a lot of Spanish stuff like news, music, literature or programs on TV and Radio. You will not understand most of it in the beginning. But whatever few words you can pick up will benefit you in longer run.
3. Buy English to Spanish and Spanish to English dictionaries. Digital versions are better as they are more portable and powerful, but book versions are alright as well. Keep a picture dictionary or illustrative one with you for convenience. Whenever you come across a new word, check it in dictionary right away.
4. Try making sentences out of what little you know of vocabulary and grammar. You will make a lot of mistakes like you did in your childhood with your mother language. But this is absolutely natural. Do not hesitate. Carry on and one day you will get a natural sense for it like you got for your first language.
The quickest way to learn Spanish or any other language is the immersion technique. This has been identified by the top linguistic institutions and the experts on languages. Immersion technique means not looking for translations of any word in your language rather associating words with pictures like you did in your elementary schools in pre-nursery classes. Keep listening to the native speakers and try to speak with and like them afterwards, reinforces what you have learned. This is identified as the fastest way to learn Spanish or any foreign language.