Go to Front View: Press 1 on Numpad (or use View → Viewpoint → Front).
Shift + A → Image → Reference
Choose your image file (JPG, PNG, etc.)
It will appear in the 3D View as a flat image plane.
Move/scale/rotate like any other object.
Use G to move, S to scale, R to rotate.
The image will not render — it’s for modeling only.
Can be locked in place using the outliner (click the 🔒).
Select the camera.
Go to Properties Panel → Camera Tab (📷 icon).
Scroll down to Background Images → Enable checkbox.
Click Add Image → Open and select your file.
Adjust opacity, scale, and placement.