How do you develop your knowledge of English and keep up to date?

It is important we develop our knowledge of English and keep up to date with new methods, vocabulary and ideas. 
Here are some ideas:

• read a lot
• listen to English program in a radio, such as Kang Guru radio
• watch film and video clip
• speak English with native speakers
• take course
• use a good course book
• use a good grammar book and dictionary
• listen to music
• use free Kang guru materials on the Kang Guru website

 Do you have any suggestions?

Sumber: Kang Guru buletin