I suggest you create a routine of learning 2 new words every day and writing them on a notebook. Then revise the words of the week at the end of the week and the words of the month, at the end of the month. Listen to podcasts whenever on the bus/train or doing actions like organizing, cleaning, etc. You can study Grammar, reading and writing all you want on your own, but regular classes with a teacher are vital to practice speaking and be corrected on the spot. That's a good start!