08-13-2017, 07:48 AM
The hard edges are the layer edges, might have been that way originally, or maybe came from a selection or crop from a larger image. You could do with a slightly wider image of the person.
Hopefully you have something like this (a quick reconstruction) with all the elements on layers. If you have a single layer, start again. http://i.imgur.com/mqOJW1H.jpg
With the 'person' layer active, add a layer mask Layer -> Mask -> Add Layer Mask Choose the first (white) option.
Click in the layer mask icon to make it active. It gets a white border when active, so not always obvious. (There is a black border when inactive.) You click on left and right icons to swap between them.
Select a fuzzy brush, set a large size 150 - 200, carefully paint on the canvas in black to blur the edges. If you make a mistake, paint it out in white. The X key swaps FG to BG and back - or use the arrows icon over the FG/BG icons in the toolbox.
Hopefully you have something like this (a quick reconstruction) with all the elements on layers. If you have a single layer, start again. http://i.imgur.com/mqOJW1H.jpg
With the 'person' layer active, add a layer mask Layer -> Mask -> Add Layer Mask Choose the first (white) option.
Click in the layer mask icon to make it active. It gets a white border when active, so not always obvious. (There is a black border when inactive.) You click on left and right icons to swap between them.
Select a fuzzy brush, set a large size 150 - 200, carefully paint on the canvas in black to blur the edges. If you make a mistake, paint it out in white. The X key swaps FG to BG and back - or use the arrows icon over the FG/BG icons in the toolbox.