You can read the full article on OUP ELT Global Blog.
The best warm-up activities are all about getting students engaged, and providing them with new interesting ways to work together and connect. They should make the students feel stimulated and allow for personalisation where possible. Don’t error correct during warm-up activities. The emphasis should be on fluency and building trust and rapport. Here are some great warm-up activities suitable for teens and adults to get your classes off to a flying start!