I have no prior experience with marketing, however I've previous helped bring in some influencers for a college event which turned out to be a success. The most effective method was to check their credibility and then make an approach, upon acceptance of the offer it's extremely crucial to keep a check on the task being performed as satisfaction of both the parties is of utmost importance.

The right influencer can be identified by reviewing their social media handle, checking their previous collaboration, checking the company's experience of working with them.