There is no specific amount of time that one must play dead in order to stay alive, as it depends on the situation and the predator's behavior. However, some general tips for playing dead include:

- Remain completely still and silent.

- Avoid any sudden movements or sounds.

- Close your eyes and relax your body.

- Breathe slowly and shallowly.

- If the predator begins to walk away, stay still until it is a safe distance away.

It is important to note that playing dead is not always an effective strategy, and there are some situations where it may be better to fight back or flee. For example, if the predator is a small animal that is not likely to cause serious injury, it may be better to fight back. Additionally, if the predator is actively attacking, it may be better to flee.