If you haven't figured it out yet, influencers are the modern-day version of Hollywood superstars.

Unlike celebrities who can only open or close a movie, influencers have broad appeal across all demographics. Whether it is a hot new shoe from Zappos or a classic pair of Levi's, an influencer may be behind it.

One can hardly walk down a street without seeing the t-shirt of an influencer pop up.

They also can be involved in the content creation. Influencers can provide keynotes, host podcasts, and offer classes.

Through content creation, they can bring awareness to brands and serve as a virtual host to a company's corporate social media accounts.

In the world of marketing, influencer marketing is one of the top paid outbound marketing channels. According to Adweek, in 2017 "more than $1.5 billion was spent on influencer marketing."

The influencer marketing industry is growing

The influencer marketing industry has been rapidly growing in the last few years. We can see this by the number of people from this pool gaining millions of followers on social media platforms.

According to Hubspot, in 2015, marketers were spending less than $1 million per year on influencer marketing and reached just 150,000 people on social media. This number rose to $26 million in 2015.

In 2017, that number climbed to $135 million and stood at more than 400,000 people.

But what does this mean for influencer marketers?

As the number of influencers increases, so does the need to ensure your influencers have your brand's best interest at heart. Luckily, there are many different marketing platforms that are easy to use and cost-effective, which provides marketers with a large talent pool with which to choose.

Over 80% of brands now use influencer marketing and the number is expected to rise to 80% by 2019. According to 1 Million Insights, in 2017, influencer marketing generated $6.3 billion.

With the number of influencers rising and social media increasing, it's likely this number will only continue to increase.

Influencer marketing is also in high demand among the millennial generation. Earlier this year, a study by Avocado Intelligence found that 92% of millennials use influencers as their first source for buying decisions, and 80% of millennials trust social posts.

In this particular study, 85% of millennials surveyed were willing to pay $200 for a limited-edition box of avocado toast that featured an influencer's face on the packaging.

Finally, every company benefits from the reach and frequency of influencers. As social media platforms evolve, and the digital footprint grows, each company has the opportunity to reach more customers than ever.

Do your homework

Before spending any money on an influencer campaign, it is always a good idea to first take a close look at the influencer's social footprint, reach, influence, and credibility.

To do this, it is best to utilize tools like Social Intelligence from Return Path. This tool allows you to run a large number of tests, helping you select influencers that you are confident will be relevant to your business.

You can also run focus groups, customer polls, or surveys with your current customer base to discover the ideal influencers.

It is also important to note that the authority of influencers and the credibility of influencers matters. Consumers tend to trust higher-quality sources over less-credible sources.

You should also know that influencer marketing is not a one-size-fits-all solution. You should consider different influencers based on a variety of factors, such as your product, target audience, and budget.

Finally, it is important to remember that no matter how successful your influencer marketing campaign is, it will fail if the influencer fails. If you have hired an influencer, it is your responsibility to ensure that you are communicating with the right person.

If you hired a celebrity or a model, you must make sure you communicate with them. If you hired a business professional, you must communicate with them.

How to hire the right influencers

While you may have a lot of influencers in mind, it is important to also look for the right influencers. To do this, you can leverage tools like Followerwonk, which allows you to filter influencers based on popularity, engagement, community, relationships, activity level, and more.

Most importantly, ensure that you spend time working with your influencers to ensure they are happy and satisfied with the campaign. You can do this by ensuring that they are on-board with your campaign and ask them for feedback.

It can also be helpful to share the campaign goals with your influencers and hold monthly or bi-weekly meetings to ensure that the campaign is progressing well.

What to expect from an influencer campaign

This is a question I get all the time and is one of the most common questions I am asked about influencer marketing.

As I explained above, the goal of a successful influencer marketing campaign is to drive sales. While a campaign can be successful with a lot of different purchases, if a campaign is based around a specific product, the outcome will be significantly different.