If you frequently find yourself adjusting the blend mode of layers in your Photoshop document, you can save yourself some time and mouse scrolling by using keyboard shortcuts instead. With the layer you want to adjust selected, cycle through blend modes by hitting Shift + (plus) or Shift – (minus) to drill down through the list and have the mode applied to your layer. If you frequently use Multiply as a blend mode, you can set it by hitting Shift + Option + M. Or Shift + Option + C for Color mode.