As someone who had to learn Spanish for work, I strongly believe that many 'mainstream' methods such as Duolingo or Rosetta Stone aren't particularly helpful in learning how to speak a language.
First, they overemphasize nouns instead of verbs. Second, they do not start by the most frequently used words in a language. Third, they do not focus enough on letting the user speak. So they'll teach 'the man', 'the woman', 'the child', 'apple', 'orange', 'city', and 'street'. What are you supposed to say with those? ' Child' 'man' 'apple' 'city'? How often do you actually say 'the woman' in everyday conversation? It might sound tough, but I've never seen anyone who started with Duolingo able to handle an everyday conversation.
Instead, I believe one should teach to hear and repeat the most frequently used words in a language, with an emphasis on 'brick words', words that can be reused in a large variety of contexts: "I can", "I need", "I want", "you have", "you can", etc.
Synergy Spanish is such a method for Spanish. I highly recommend it. I can honestly say I was able to speak more after 5 hours of this methods than 20 of Duolingo and Rosetta Stones. It was invaluable to help me work and travel to Guatemala and Colombia.
Because I was frustrated that no such methods existed in French, I started to build my own. Here it is below. Enjoy, and please let me know what you think!