To add a Facebook pixel to your website to monitor traffic from Facebook, please follow the instructions provided by Facebook in their article here:
To add the code generated to your PromoteMyPlace website:
Once logged into your account, click into Section 1 - Website Basics > Code
Paste the code provided by Facebook in Step 1 of their instructions to the Code - Header field provided:
Then click Save.
You can check the code is working in Facebook, by following Step 3 of their instructions.