When mapping a product for DFP there are a few steps involved. The reasons for this is due to how your adserver has been configured and each publisher does this differently depending on their site or network structure.
The first section to the mapping process is to define the account (network), placement or ad unit, device and weighting for the product.
You will have the option to map either to placements or ad units. When it comes to the priority (also known as the weighting) this is optional as well as devices.
The next part is also optional and does not need to be filled out if it does not apply to the product.
Here you can allocate the creative adserving strategy and how you want them to appear on site. The other options are to include or exclude keyvalues. These can assist with how the product is positioned on the site and where.
Next part is to define the geographical location of the impressions that you wish to allocate at the product level. This section is also optional and if nothing selected it will simply allocate all impressions regardless of orientation.
This section allows you to assign a placement naming convention based on merge tags which are pulled from the database. Here you can construct a string of variables to define how things are named when pushed into DFP under the campaign level. If you don't insert anything it will allocate a default for you.
The last part is the forecasting information based on all the settings you have allocated at the product level. The estimate impressions are based off a 30 day forecast. If in the case you receive an error, please reach out to firstname.lastname@example.org for assistance.