To fill formulas automatically without needing to drag through the cells, you can use a combination of copying and pasting techniques with shortcuts. First, enter your formula in the initial cell. Press 'Ctrl + C' to copy this cell, then select the target range for the formula. Press 'Ctrl + V' to paste, and the formula will automatically adjust according to each cell’s relative position. This is useful for large datasets where dragging the fill handle is impractical.