Try to minimize your use of "have"

Use this link in order to better understand the use of tenses. I probably violated couple of them in my correction also, switching from present continuous tense and so forth.
http://www.englishpage.com/verbpage/verbtenseintro.html

I have been learning English for many years, mostly by myself. This year, I started studying English in an intensive manner. I listen a lot, and I practice speaking when I am alone. I am trying different methods, but speaking and listening are the most important methods to me currently. After I accelerated my studying method, I noticed that I have been making a lot of mistakes due to my approach to learning. Now, I am trying to fill the gaps in vocabulary and grammar.
I wrote this text without any dictionaries or any other help (aid), to indicate my possible mistakes. :) Please, be understanding.