Start by creating a Multi-Step Journey.

Select your entry point for customers. In this example, we are using a data extension.

Once you have selected the data extension you are sending to, you can define a schedule.

It is important in the schedule to define a Run Once journey, as this will allow you to specify a hold out group in the Path Optimizer configuration.

Once you have configured your entry data, you can add the Path Optimizer activity to the journey and configure your test.

For email, select email engagement and select the metric used to determine the winning path. Normally, open rate is recommended in initial Phrasee experiments. It is also important to set the test time here. The recommended test time is four hours.

Salesforce will automatically divide your test audience up equally, so you don't have to edit the percentage in the Split settings. All that is needed here is to add a path for every subject line being tested.

In the holdback settings, you want to configure the test audience size as suggested by Phrasee when you created the experiment.

Once you have everything configured in the test setup, you can add your emails.

Now, add the email activity to each path on the Path Optimizer and configure the subject lines.

After selecting your email:

Copy and paste the subject lines into each email.

Once you have completed the configuration of all the emails, you can activate your journey which will either start automatically or on the configured schedule time.

During the testing phase, you can check on progress by clicking on the Path Optimizer activity.