To "draw in" a guide in creative software like Procreate , you typically use built-in "Drawing Guide" tools to create a framework—such as a grid or perspective lines—that your strokes can snap to for precision. How to Create Drawing Guides (Procreate Example)

: Draw a square grid over a reference photo and a matching grid on your canvas to help transfer proportions accurately.

: Tap Edit Drawing Guide to choose your specific type: 2D Grid : A standard square grid for general alignment. Isometric : A triangular grid for 3D technical drawing.