How can I transfer a graphic onto metal?

Here is one I found that is a tutorial for both metal and wood. I hope this helps for your metal project. https://www.hometalk.com/diy/decorate/rooms/transfer-vintage-graphics-amp-photos-to-wood-and-metal-1096827

Transfer Vintage Graphics & Photos to Wood and Metal

Here is a tutorial for using modge podge to transfer images onto metal https://modpodgerocksblog.com/metal-photo-transfer-art/

https://dfarq.homeip.net/transfer-an-image-to-metal-with-paper/

https://empressofdirt.net/image-transfer-methods/

Depends on the image. I usually use printable temporary tattoo paper to transfer my images to hard surfaces - there are a few types - one with a white background, a metallic background and another with transparent background - I've attached 3 tutorials (one of each): https://maritzalisa.com/diy-tropical-leaf-patterned-clipboard/ (transparent) and https://maritzalisa.com/diy-vase-with-a-white-flower/ (white), and https://maritzalisa.com/diy-ring-dish-gold-tattoo-paper/ (gold)

Hi, there are a lot of great image transfer mediums out there. You spread it on your paper and then put the paper onto the metal. Wait 24 hrs until it is dry and then gently wet the paper and rub until the paper comes off. The image will remain on the metal.