Final Image
Original Image
Step 1
Firstly you must find blood photo. Like this:
Link
Step 2
Open the picture. Crop a blood using a Polygonal Lasso Tool.
Step 3
Cut (Ctrl + X) and Paste (Ctrl+ V) at Lady Gaga layer. Then re-size the blood. Just press Ctrl + T.
Step 4
Maybe you can add more blood effects or another effects. Like this:
Step 5
Using Rectangular Marquee Tool, crop the accident effects photo. Same step like step 3.
Step 6
At the same layer change mode to Multiply.
Step 7
At the same layer, go to Image > Adjustment > Brightness /Contrast
Step 8
Then click at Eraser Tool, choose a soft brush. Depends your photo size and resolution. For this photo, I choose 100 px soft brush.
After retouched..
Step 9
For the blood layer, go to Image > Adjustment > Brightness/Contrast.
Step 10
At the same layer, Go to Image > Adjustment > Vibrance. Finish.
Final Image