Check out Influenster. It's a site where you review products you already have used and you receive points for those reviews. Every month they pick a large group of members to review a box full of products, I was picked my first month into the program. This is the site Influenster.com.
I am signed up with the program and here is a review on one of the boxes they recently sent out that I recieved
L'Oreal also has a product testing panel you can sign up for right now. Just fill out the quick survey and if you need there match then they will send you an email. Here is the link
As for getting signed up with companies, I know a few people who just sent an email to customer service. All that was required of them was to show their average daily views of there blog/youtube channel and how many active followers they had.
Hope this helped a little! Good luck!
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