1. LanguageTransfer
If you are a native English speaker, there is nothing I recommend more than the 100% free resource LanguageTransfer. The principal works by its namesake, finding ways of converting English words and thought processes to Spanish through reviewing roots and origins.
I am not a huge fan of podcasts, but this improved my conversational Spanish greatly. It also has an app on iOS and Android which is even better!
2. Spaced Repetition (Flashcards, Quizlet, Anki)
Look, you have to get vocab somehow—especially if you are unable to practice everyday with a native speaker. On this website, at the bottom of each page, I offer some printables and also links to Quizlet and Anki cards to practice.
These helped me hammer down my vocabulary, and I highly recommend pursuing some form of spaced repetition. My weapon of choice is of course Anki but they all operate by a similar principle.
I also used Duolingo, and the gamification of the learning is fantastic but I found it difficult to tailor it to what I needed (learning how to interact with patients in Spanish).