NOTE: This effect will come out different each time. Sometimes it will look great sometimes it will not look so great.
This is a sample output:
Step 1: Start with a blank document. I used 300x300
Step 2: Write the text wished to be written in blood.
Step 3: Duplicate the layer.
Step 4: Select the bottom layer and add a jitter to it.
Step 5: Get rid of the jitter above the letters.
Step 6: Add a motion blur to the jitter layer.
Step 7: Add a motion blur to the text layer with less blur this time. I used 11 for distance.
Step 8: Merge the layers together and add a gausian blur.
And as always, here's a cool effect you can add on.