First, you got to find the right influencers. Use Keyword Tool for Instagram for searching them.
Next message and cut a deal with them. Finalize how much you’ll be paying them.
Instead of big influencers, go for micro-influencers. Those with 2000-5000 influencers with engaged followers.
Because they usually have better engagement than mega influencers.
Even better you can become an influencer yourself and get other influencers to promote your account and product. You can do the same.
The more you practice this, the more proficient you’ll become.