First step is to find a photo that you want to use. Hopefully it’s of a white t-shirt and front forward.
Next step is to open it up in Photoshop and unlock the layer.
Create a mask layer with the layer mask of the model.
Next go back to the layer of just the T-Shirt select just the T-shirt by loading the selection we had previously save.
Ctrl D to deselect the T-shirt and make the T-shirt level visible Your almost done. All you have to do is drag and drop make you want on the T-shirt. I open up and Image Ctrl A to select all and than press ctrl C to copy it.
You might want to use the Transform tool Ctrl T to change the size and rotate it to fit on the shirt better.