Please go to My Account > Integrations & API > API Keys > CREATE API KEY:
Name your API key WisePops and click SAVE:
Your API key has been created!
Copy this long code as you will need it.
Now, go to WisePops editor and click on Edit icon on your signup form:
Click on tab Sync and you will get displayed the options to select your Email marketing platform. Click on Soundest:
You will now get the option to enter the API key:
Paste here the API Key and click Submit.
As a last step you will need to set the list in Soundest you want to collect the subscribers - the best would be to create a custom WisePops list:
Save changes - Done! Your integration is now complete.