Ask yourself a question: why am I learning English? Having a strong motivation can really help to keep going in difficult times. When you identified your purpose, remind yourself about it every time you get reluctant to learn something new. Having a clear purpose in mind will move you forward. Motivations behind learning can vary: immigration to an English speaking country or being able to speak to your partner. Perhaps, you want to be able to study abroad, which requires the knowledge of academic English. Or, maybe, you are passionate about languages in general, and you want to crack a code of another language in your collection. Some people need to be proficient in highly specialised skills, such as talking about maths in English, or presenting an architectural project to an English-speaking audience. Your reason for learning is very personal, and only you can identify it and have it as a beacon shinning a light on the unknown territory.
Once you got the motivation under your belt, we can get to work. Of course, in order learn fast and learn for good, it is imperative to surround yourself with English: speak it, write it, listen to it, read it. But it is also important to counterbalance your intense studies with something else: for some students it is speaking their native language, for some it is doing sport, for others it is learning another language. The basic idea is to have an occupation that will be as immersive as learning English. When you switch your attention from one subject to another, you will be able to focus better and get the most of your studies.
The trick here is to dedicate your full attention to studying one thing: it is akin to meditation when your mind is free of distractions; you envision your final goal and motivation; you are moving towards it, smoothly, without interruptions until you need to take a break. During your break you need to switch your mind completely to something else, and that’s why doing sport or communicating in your native language can provide this experience. I think, creating conditions for this way of learning English is a key to reaping long-term benefits from acquiring the language.