> For the complete documentation index, see [llms.txt](https://emotiv.gitbook.io/flex-2.0-user-manual/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://emotiv.gitbook.io/flex-2.0-user-manual/setting-up-flex-cap/fitting-flex-cap-to-a-participant.md).

# Fitting FLEX Cap to a Participant

Fit the FLEX Cap to your participant’s head like you would fit a swimming cap.  

1. Place the FLEX Cap over your participant's forehead, ensuring the pocket for the FLEX Controller is at the back of the head.
2. Stretch FLEX Cap to the back of their head. 
3. Make sure their ears are placed through the ear holes.  
4. If your participant has long hair, make sure that it is spread out evenly across their head so that there are no thick sections. Your participant’s hair must not be tied up during the experiment. 

When the FLEX Cap is on your participant’s head, they should feel the pressure of each sensor against their scalp. If they do not feel pressure from the sensors on their scalp, there might not be enough tension in the FLEX Cap. If this happens, then try fitting a smaller FLEX Cap or move the chin strap to see if it becomes more tense. 

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