Demonstrate the lesson point with the JTE. I usually do some gesture such a 'playing tennis' or 'reading a book' and the JTE asks the class what I'm doing. The JTE will write the answer on the board 'He is playing tennis'.
Make groups and select order. Take turns with the JTE. One directs the class to ask 'What is ... doing?' and the other does the gesture. The students rush to raise their hands to answer 'He is swimming'. If they make a mistake such as 'He is playing swimming' I'll either correct them and give them a point or let another team have a chance to steal the point. Once the answer is given, give that team a point, and switch roles and do another round with the next student in each group guessing.
After a few minutes I start calling on students. Volunteers get 2 points for their group if they come up, take a gesture card and do the gesture. Again before they do the gesture the teachers get the class to ask 'What is ... doing?'.
After a few rounds of that if there are enough volunteers I'll have two come up at once so they can practice 'What are they doing?' and 'They are ...ing'
If the class is really shy I pretty much just stick to teachers doing gestures (This is almost never the case) and end after 12 rounds. If the class is really into it I'll keep it going for half the lesson before moving onto a writing activity.
After this the cards can be given out to students and they can mingle, make pairs and do the gesture and the other guesses 'are you ... ing?' and then switch cards and make new pairs.
The excel cards I use are from my old office. I've no idea who originally made them. If they pop up in the Englipedia archive I'll link the activities.