To use Walmart Promotional Pricing all you need to do is add in an MSRP. Your listing will reflect a "List price" in blue and "Save $X" in red. It will also have a blue box that says "reduced price".

Remove

Through the User Interface

1. Go to your Catalog Page
2. Click on "Catalog" in the top left drop down and select Price
3. Search for the SKU(s) in question
4. Hover your mouse next to MSRP and click on the grey box 
5. Enter in your MSRP

Through an Import

1. Create a Template with SKU, Sales Price, MSRP
2. Export the Template
3. Add in the pricing information
4. Reupload the report