One of the best ways to be fluent in any language is to have a regular interactive session with a native speaker of that language. Failing that, another alternative is to listen and practice using the language using a recorded voice together with the written transcript of the recording.
Filipino is the official language of the Philippines. It is also the language spoken by the majority of Filipinos. While anyone can get along using English while staying in the Philippines, foreigners who can talk in Filipino will have a definite advantage over those who are clueless about it. For example, you will be less likely to get scammed if you can understand what the people around you are talking about. Immersing yourself deeper by going into the intricacies of the Filipino language will enable you to get better acquainted with the culture and the thought patterns of the Filipinos. As with all other countries in the world, having a firm grasp of the language spoken by its citizens can make your life easier and get you farther in what you intend to do.
Knowing English would already give you an edge when learning Filipino because a lot of English words have been assimilated into it. The Philippines had been a colony of the United States of America for several decades resulting in the adoption of certain aspects of the American way of life giving way to American ideas getting embedded in the language as well. The Philippines had also been colonized by the Japanese but only for a short period of time leaving behind almost no influence on the Filipino language.
Knowing the Spanish language can be useful if you intend to learn Filipino. The Philippines had been colonized by Spain for several hundred years and consequently a lot of Spanish words and phrases have been deeply ingrained into Filipino, although their meanings have changed from their original significance in the Spanish language. Some Filipino words can be traced directly to their original Spanish counterparts.
Filipino as a language is not as complex as the other languages. Unlike Spanish, verbs are not as sensitive to the number of actors in the subject and they are also immune to any change when the sense of the sentence is expressed in the negative. In Filipino, the verbs are in most cases conjugated only with respect to the time when the action or event is taking place. In this sense, it would seem that Filipino can be easier to learn than some other languages like English or Spanish.
However, the Filipino verb can change its form very easily to shift the focus of the thought on another doer thus transforming completely the idea being imparted. This makes the Filipino verb a powerful language construct but unfortunately makes the Filipino language less easier to learn. Learners can get confused on how this changing of the form is being done which to native speakers seem very intuitive and natural.
So those are my thoughts on learning the Filipino language. Incidentally, there's an innovative web site that provides free Filipino language online learning lessons in the Internet. The lessons are delivered online with the textual and the audio components combined on the same page. You can listen to some of the lessons there at: http://sites.google.com/site/learnmoretagalog/.