Many of these NIL deals won't look too much different from what has gone on in social media for years now. Basically, if you've got enough social media followers in a place like Instagram, you might get sponsored by someone, which gives you money and or merchandise in exchange for an obligation of promoting the sponsor.
So for someone who isn't a massive multimillion dollar investment (and I can safely assume Liv is not), it probably means that she makes some periodic posts on Instagram, etc. wearing the product or talking it up, plus maybe a few more professionally produced videos or whatever, based on that same concept of promotion.
Collegiate athletes couldn't do these deals before even when their following was large enough; now they can.