Grids are are excellent way to draw up your composition with accuracy. The more complicated the drawing, the more grid tiles I use.
Drawing freehand is fine and is a method that I still employ from time to time, but grids are far more accurate.
Today’s photo of a slice of bread is a good example of when a grid is needed. The bread is now a landscape feature, actually it’s a section of coastline. It is vital to get the proportions right, hence the employment of a 32-tile grid.
How do you draw up your art?