Use repetition and mimicry. Teach phrases and have the students repeat them to you and to one another to help the students get accustomed to correctly using English grammar, sentence structure and pronunciation, which will help develop the habit of speaking fluently. Encourage them to develop memorization skills, as they won't be using written English or taking notes. Use photos and props to teach new vocabulary.
Provide opportunities for your students to interact with native speakers. Have students participate in natural conversations and spontaneous self-expression in real-life situations in English to practice their communicative English skills and build confidence. If you are teaching in an English-speaking country, go on a field trip to a cafe or store. Have the students order something and use numbers. This is an especially effective exercise for those who usually have English speakers shop for them, or those who live in a community where they speak in their native language. Prepare them with some basic phrases appropriate for the trip and have them practice in class before the trip.
Invite a native English speaker as a guest. Bring in someone with no experience in teaching EFL. Get your students used to natural speech by encouraging interaction with as many native speakers as possible. Ask visiting friends or family members to come talk to your class. This is especially effective if you are teaching in a non-English-speaking country, as your students will appreciate the rare opportunity to interact with native speakers. Have the students interview the class guest about their home country and share something about their own.