There are myriads of books about how to study English. This reflects the extent to which Japanese people are interested in the language but I think it has gone so far as to make them need a guidebook about how to choose which book to buy. Now it goes without saying that language changes as time goes by. Accordingly, I heard criticisms against those books which were written some decades ago. The critics say it is true that these books are fine but the English expressions in them are obsolete. They don't deserve studying, so the criticism continues.
Granting that the first point of it is valid, the conclusion doesn't necessarily follow from it. My experiences have shown me that so-called "old" books are often written by earnest students of English who knew how arduous it is to learn a foreign language, experienced the difficulty in its entirety and came to have an unprecedented command of it. They teach not only about the English language per se, but also proper attitudes towards it. And I have never seen a book published recently that manifest such attitudes. The authors refuse to face the difficulty and try to tell the readers an efficient way of learning it. It is lamentable that mere techniques should be endorsed instead of these attitudes.
The books I believe express them are as follows. They are old and hard to come by, but worth the effort.
This is a book on German but I think it too lets you know what I have written about so far.