Create a Custom Audience

After installing your pixel, the next thing you need to do is to tell Facebook the audience that you want to retarget. Here, you’re not restricted to just demographics while selecting your audience. Instead, you can group your audience based on similar actions they’ve taken on your website or what stage of the customer journey they are currently at. For example, you may decide to target people who visited your website but didn’t make a purchase.
Here’s how to go about it:
Sign in to your Facebook account and select Ads Manager from the sidebar of the homepage.

Select the hamburger icon and click on Audiences.

Click Create New Audience and then Create a Custom Audience

Next, you’ll be asked to choose your traffic source.

Website

If you have a pixel installed on your website, select this option to create an audience that consists of people who visited specific pages of your website. If you choose this option, Facebook will ask you to select specific criteria for your audience and a time frame that qualifies them for retargeting.

Decide whether your audience must meet one or all of the conditions you set. For this example, we select “All” from the drop-down

Choose which visitors you want to be included in your audience using the drop-down.

You can include anyone who has visited your website, visitors that only viewed individual pages, or a combination of pages. Now enter a timeframe in the past 1 to 180 days. For example, we select “All website visitors” from the drop-down and leave the default “past number of days” at 30

App Activity

If you have a mobile app for your business, this option is for you. But to effectively track users’ activities on your app for marketing purposes, you first need to install Facebook SDK to your app. You might have to work with your developer to have it installed.

Customer List

This option allows you to upload the details of your target customers in the form of a CSV or TXT file.  This is an excellent option for you if you use a CRM service like Hubspot to manage your customer data. If you use MailChimp, you can also import your customers’ information seamlessly.

Offline Activity

Facebook also allows you to target audiences from offline activities like in-store purchases, phone sales, etc. You’ll have to manually record their details whenever they meet the criteria that qualify them for retargeting.
As your campaign runs, try to update it with any new information you get from your physical “events” so that you can accurately track which ones your ad campaign is responsible for. This way, you’ll know how your ads are performing.

Facebook Sources

Select any of the appropriate Facebook sources displayed if you want to retarget people based on their engagement with your Facebook or Instagram posts or previous ads.