I think it depends on your learning style. For me, I need to understand basic grammar in order to know how to construct sentences, form plurals, conjugate verbs, etc. I also want to know basic pronunciation and common words such as greetings, colors, numbers, parts of the body, etc. Trying to learn these solely by listening would leave me totally confused. A few years ago I took an immersion Spanish class for two months in an effort to improve my Spanish. It was a total bust. The idea behind their teaching method was that babies don't learn grammar rules in order to learn to speak, so we shouldn't either. But I'm not a baby--I'm an adult who can read, write, and study. I can accelerate my acquisition of language faster than a baby can by doing all of those things. Moreover, the four hours a week spent in class were not nearly enough of an immersion for me to naturally improve my skills. Ultimately, I think a multi-faceted approach works best for me. I try to spend at least 30 minutes a day on Spanish, at least five days a week. I study grammar, read magazines and Wikipedia in Spanish (silently and aloud), take notes and memorize vocabulary, watch YouTube videos (instructional and entertainment), and speak Spanish as often as I can, even if it's only to myself :)

Hello there Mr Jones what is your mother tongue and what language are you trying to learn ? I would say the most important thing to remember when just starting off is to listen to that language ever day for at least 30 minutes per day consistently, no matter what. Listening to music for 30 minutes each day is a goal that can be achieved quit easily

If I start learning a language from scratch, I first learn some basic phrases (introducing myself etc.) then basic nouns and verbs, and really easy grammar (the conjugations of these verbs in simple present and past, personal pronouns, maybe the genitive and dative case of nouns.) Then I would start talking, using these words. I would make simple sentences. After that, I'd learn a little more vocabulary and grammar, then use these in simple dialogues, then learn more words, and talk more. So grammar and speech are both important.

Hi, how are you? If you learn grammar first then you won't have to go back to those lessons again, the ideal path is to learn everything at the same time, but is really hard, so, practice your grammar and the start practicing your speaking, but you'll have to go back and check your old lessons every once in a while. I studied in Canada, they gave us a lot of grammar everyday, I'm really grateful of that way of teaching, they never allowed us to forget what we were practicing, I really appreciate that effort, now, I feel really competent about grammar. Practice your verbs, that'll help you a lot. Once you master grammar, your speaking will improve for sure, but you have to master it, so you learn the lessons that will improve your speaking, if you know a lot of grammar your speaking will improve, it might sound crazy but there are plenty of grammar lessons that'll help you to speak better.

Reading and listening are always the most helpful things for me. I occasionally read about grammar rules to make sure I'm understanding certain concepts. To get better at speaking, I would listen to recordings of native speakers and repeat what they say. Choose certain sentences and keep on repeating them for practice.