Place the cursor where you want the line.
Go to the **Home** tab.
In the **Paragraph** group, click **Borders** (or **Borders and Shading**).
Choose **Horizontal Line**.
If needed, adjust the line by selecting it and changing the **width/color** options in **Borders**.
Alternative: Go to **Insert** tab.
Click **Shapes**.
Select a **Line** shape.
Click and drag to draw the line.
Alternative: Type three hyphens (**—**), then press **Enter** to insert a horizontal rule.