Read English newspapers or magazines. Circle the new words and write them on a separate page. Later on find the meanings of the words with synonyms. Practice makes perfect. Keep this practice continue for months. Secondly, cram the noted words daily and use them in your writings. I did this practice for 2 to 3 hours daily and still I collect new words and memorize them.
Regards

__________________
Try not to become a man of success but a man of value.