- In the UV Editor, name your image data block (e.g. “Monkey”)
- In the Properties panel, go to Material
- Create one if it doesn’t exist. It should say Surface: Principled BSDF
- Click the white dot to the right of Base Color, Select Image Texture
- Click the image icon to the left of +New, and select your image data block, “Monkey”
- Make sure your viewport is in Lookdev or Rendered mode. Eevee/Cycles doesn’t matter.
Later on, you’re likely to save your image texture to a file in #1 and/or may reference a file with Open in #5.