Influencer marketing is to promote our product or brand via people who has good follower base on social media.
You should select the influencer on the basis of target audience of the product. For Example our product is from cosmetic category we should select Influencer from Beauty and Life Style.
Since bloggers have huge follower base on social media, they can create brand awareness via content creation. More over the trust the followers have toward the influencer is higher and the scope of sale for an endorsed product is higher.
Brand only need to provide objective for the campaign. Content creation will be handled by the Influencer.
We can judge the quality of Influencer with their Engagement ratio on social media.
We can ask influencer for insight of our brand post to check the exact engagement of our post.