Learn the alphabet. If the person is not familiar with English letters start by learning the alphabet. If they know the letters then practice pronunciation of the letters. For example, the letter "A" is pronounced a few ways.
Teach basic English phrases. "Hello," "goodbye," "thank you," "please," "my name is ..." and other commonly used English expressions should be taught immediately, as these are needed in any English-speaking country.
Begin forming basic sentences and teaching vocabulary. Deconstruct sentences and teach how to form sentences. Subject, verb, noun and other lexical categories should be taught, along with how they are used. The person will unlikely remember them all right away but they should know where they go in a sentence.
Practice forming basic sentences. Start by including tenses in sentence construction. Have the student repeat sentences she has formed aloud. Introduce more vocabulary. Have the student read English children's books, as these are easier to grasp at first. Have the student write a list of vocabulary words and create her own dictionary.
Practice, practice, practice. Have the student read, write and speak English as much as possible.