Right click and select Edit In, then select Open as layers in Photoshop.Command or control select both images ( original and the copy ).
With the copy image ( with the preset effect ) selected change the opacity to your favorable percentage. In my example I changed the opacity to 70% which game me exactly the effect I needed.
At the end make sure you change the option of saving as Photoshop file. Save your work to your desirable format, I usually use PNG. I hope this tutorial was helpful.