Step 1:

On the panel on the left, hover your cursor over "↗" ICON to open the drop-down menu. Click on the "flat-end arrow" to add it to your canvas.

Step 2:

To rotate the line, drag it by the corner handles in the direction you want.

Step 3:

You can make changes to the color, thickness, and ends of the line in the EDITS PANEL on the left.

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