Blending Modes

Blending modes are key in Phtotshop. You can go without, but they will do amazing things!

• When you want to add something in a subtle way, be it an object or coloring, use Overlay.
• Use Hue, Sat., and Lum. ones to add said properties of one layer to another.
• Difference and Exclusion invert colors and give unusual, but sometimes cool results
  

You can select the first normal, and then use the down arrow key do flip through them* until you have one you like.
*Flipping through them makes undo steps, of which there is a limit. Don't do it if you might need some undos!

When you want to combine two layers, blending options is the way to go.

Also try:

• changing either layer's opacity
• reversing the order of the two layers
• inverting the colors in either layer
• changing the modifying(top) layer's brightness/contrast

You'll get to see a cool example soon!