"Behavior is the expression of the problem, not the problem"
~ Daniel Amen.
One of the first things you can do is to keep pain at an absolute minimum. The combination of an inability to communicate information quickly, and pain, can cause a TBI survivor to lash out physically. What may seem like nothing, hair brushing, sitting on a hard chair, can be extremely painful for a person with a TBI.
Speed - Speak slowly. Move slowly. Be careful not to cause an information traffic jam. The ability to get information in and out of an injured brain has been greatly reduced. Slowing the flow of information is essential in lowering stress and frustration. The same holds true for physical movement, turning over in bed can feel like being "shoved". Slow it down as much as possible.
Schedule Knowing what, and when it will happen, can greatly reduce anxiety and worry. Set a schedule and stick to it.
Simplicity One thing at a time. Multitasking is stressful for injured brains. Try to focus on completing one task at a time. Even having too many types of food at a meal can be distracting. One thing at a time if you notice focus becoming an issue.
Sounds and Sights -Loud music and bright light can cause massive amounts of stress. Keep the lights as dim as possible and keep the noise level to library mode.
Speaking - When speaking to someone with a brain injury: Care don't correct. Accept don't argue. Reassure don't reason. Tell don't test
Sleep - Plenty of rest is essential. A well rested person is able to handle stress and frustration better than someone who is tired, this is especially true when dealing with a brain injury.
Sameness Even moving objects around in a room can cause confusion. "A place for everything, and everything in it's place." reduces stress.