Have an English immersion is the best way but it is difficult because you have to go abroad. But, you can read books, watch Tv shows, read newspaper articles, write notebooks on italki. Also, to increase your vocabulary you can begin to write new words in a book and try to use them every day. Also, try to find people on Italki who is learning your first language and you can teach him/her your first language and in exchange he/she teaches you English.

Practice every chance you get, even if it's only for a few minutes. In my opinion, a little practice but often is better than studying for several hours once a week. Try to merge your target language into your daily routine. Most importantly- don't be afraid of mistakes. They're a normal part of learning. Find a teacher, language exchange or make a new friend in the language, be confident and keep going. I also read this article recently http://learnlangs.com/700_hours_how which might give you some more ideas. For some people, keeping track of how much time they're spending can help them progress. Good luck :)