Create your text and make sure the resolution is the same as your target image and the dimensions are appropriate to fit nicely. In this case, the only reason I had a black background on the text was to see the white lettering.
With the text layer selected, press Cmd-A, to select the text, then Cmd-C, to copy it (Win: Cntl-A, Cntl-C). Now click the target image, the barn in this case, to make it active.
vanishing point
Vanishing point
Linear Mode
