How to Soften Edges in Photoshop?

Question

Adobe Photoshop

In Psd for layout there is a slider with controls back and forth. When hovering, the background of the control changes. I apply a new background to the image in Photoshop, but the edges are ugly, the borders are clearly visible, which is ugly. How to apply anti-aliasing or whatever it is called when as you approach the edges, the pixels become, as it were, more transparent

Answer 1

Maybe not the best option, but the first thing that came to mind:
1) Select the contents of the layer (CTRL + LMB on the layer preview ... well, you never know)
2) Then through Selection> Refine Edge (alt + ctrl + r) play around with smoothing and shading.
2) Without removing the selection, create a layer mask.
The advantage of this option is that the original layer remains intact.

Answer 2

This is translucency. Post a picture.

Answer 3

Select control, Selection->feathering Set to half pixel-pixel.