I think you should get a good grammar book, a dictionary and look for a partner who can help you with your english. Ah...your question is wrong, you can say: What can i do to improve my english? (You dont have to use the 'ing' form after 'can') or What i should do to improve my english? bye bye

well best thing you can do is practice by having conversation with a native speaker and read more english books

It really helps if you know other people who are trying to learn English along with you so that you can practice together. I think the key to learning another language is consistency. Practice every single day. Watch English language movies, read books in English, read newspapers in English, and so on.

Hi Daniele. This is my advice as an English teacher. I think that it is very important that you listen to and practise spoken English as often as possible so that you improve. You can click onto Language Partners and Language Teachers at the top of this page for help. These sites are good for listening and pronunciation practice. http://www.bbc.co.uk/radio4/
 http://www.elllo.org/ http://www.bbc.co.uk/worldservice/learningenglish/ http://news.bbc.co.uk/ http://www.usingenglish.com/
 http://www.englishpage.com/
 http://www.tolearnenglish.com/
 http://www.oup.com/elt/global/products/headway/
 http://www.flo-joe.co.uk/
 http://wordweb.info/free/

or "how can i improve my english?" joining italki is a good start