How do you improve your vocabulary?

Once I decided to buy the book "The Adventures of Sherlock Holmes" by Conan Doyle in English in order to improve my vocabulary. I began to read the first page and during wrote down new words which I don't know to the note. Found its translation and read this page again newly with the new translations. When I take the next page and etc (Suggestion: Then I did the same for the next page).I think this way is useful but I want to know how do you improve you vocabulary? And which books did you read in another languages?

There is a suggestion that to improve your vocabulary from reading you should only read books where you understand 95% of the text. If it's too difficult you don't learn anything! I like to read books I have already read in my own language and know well, I quite often read children's books in Chinese and it helps you to improve your vocabulary very quickly!