The Price List Evaluation Entity allows you to give granular, multi-entity definitions as to which customers should receive what prices for products. The definition of these evaluations is query based. Once you have set up all your queries, they system will evaluate each customer record when they are created or updates are made. The Price List field on the customer record will be updated automatically based on which query the customer meets.
Select a Price List or Create a New One

Click on the record you want to edit or click +New to create a new price list.
Fill in or Edit Price List Fields
Name -- The name of the price list. (This name will display on the contact record, product set up, and on registration fees on the portal.)
Evaluation Order -- Order in which a customer is evaluated for the price list. If a person may fall into the query for multiple price lists which one should be evaluated 1, 2, 3, etc. For the example you see that if the person fits the query for members, then they should receive member price list first, even if they fit the criteria for non-member or other price lists too.
Start Date -- If this price list is temporary you can set a start date for when this price list is in effect. If the price list is permanent no date needs to be set.
End Date -- If this price list is temporary you can set an end date for when this price list will expire. If the price list is permanent no date needs to be set.
Currency -- This should default to your default currency set in the system.
Edit an existing evaluation or create a new one

Fill in the required fields and save.
Name -- Give the Price List Evaluation a Name
Price List -- This should automatically populate with the price list you started from. It links the record to the price list.
System Query -- A link to the system query record.
Customer Type -- Select Contacts or Accounts
*You may have multiple price list evaluations, but generally you only need one, or two if you have an evaluation for both contacts and accounts.
Use the more options button to View/Edit the Query

Do not try to edit from the link to the system query on the price list evaluation record. This will not work.
Enter the criteria that will determine whether of not a customer is eligible for this Price List.
This is a simple example where membership is active. If you can access the field from the advanced find query you can use it in a price list evaluation query.