How can I improve my English?

I know there are no capitals in Hangul but in languages that use the Latin alphabet the difference between lower and upper case is quite important.

Are these sentences right ?

In English and in any European language the difference between single and plural is important. Much more important than in Korean.

I wanted to be good at English after I joined English camp.
I asked my English teacher the way how I can be good at English.
My teacher said that you should follow this way.
First, you should talk English with your friend.
Second, you should hear a tape in English to improve your listening and pronunciation.
Third, you should read a book in English to improve your vocabulary.
Finally, you should write your diary in English.
It gives you an opportunity to write some things in English.
It looks like very simple but I am not sure (if)/(whether or not) I can follow it all.