Make your opponent Tense.
I have come across many people who try and pull their hands out when they have been grabbed. This is also a very bad Chi Sau黐手 technique as the more you try to pull your hand out the more tension you will create in the body and the more tense you are more opportunities your opponent will have to hit you. We should not use more force against our opponent, we should be more relaxed and as long as we can maintain our distance we are safe.
If the opponent is using a lot of force to try and pull his hand out, we can actually hold their hand very strongly and they will find it even more difficult to pull it out, then they will use even more force and at that moment their whole body will become tense. This is the time to hit them and once we hit we should hit many times and so they might even lose their balance. Any skill that can make your opponent tense and afraid is usually a good skill.