This video explains how to Create Promotion

Navigate to Sales, Promotion, Create New.
Fill in the header info, i.e. Code, Name, Validity Period.
Click Confirm and Approve.

STEP-BY-STEP:
1. Go to Sales menu
2. Select Promotion
3. Click Create New
4. Fill in the header info, i.e. Code, Name, Validity Period.
(mandatory fields in red color or marked with red x)
Click Save button.
5. Add Products and their discount in the table below (Product #, Discount % or Discount Amount)
User may filter the list of products by the Product Brand.
Click + button or press ENTER to enter each line of data and saving the product line.
Remove the Product Brand filter by choosing “Select All”.
6. Right click on a product line to see available options.
Click “Show Product Details” to view the product master details in the Inventory module.
7. In the Promotion document view, click Confirm Promotion button in the Listed Products tab when done editing.
8. Click Approve Promotion button.
It will now be available in the Sales modules transactions (i.e. Sales Order).
9. In the Promotion list view, right click on one of the promotion in the list, to show available options.