One of the best books for learning vocabulary is “Barron’s essential words for IELTS”. Thanks to MODERN TECHNOLOGY, you can learn the words in the book using ELECTRONIC FLASHCARDS.
To start learning:
1 – go to this website to download the “anki” program onto your computer for free
2 – when you have the program, click on this link and download the deck
3 – then open the file and start typing in the answers
Here’s a video that shows the above steps for computers as well how to type answers in the flashcards