How to Donate Hair Via Mail

I've been growing out my hair for 4 years now, so it's safe to say it's miles (or inches heh) beyond the required length needed. That, and I've not bleached or done keratin once.

I wanted to know some specifics on how to follow through with the donation process:

1. Do I put the hair & donation form in one of those small letters? Do I have to mail it in a box?

2. I'm kind of new to US, so what is the best place to take the mail to?

3. How long can I wait to donate after my hair has been cut? (Sadly all Haircut & Donation places are far)

Any reply is much appreciated 🙏🙏 Been years since I had short hair so I'm anxiously looking forward to it 😅