To smooth edges in Photoshop, you can follow these steps:

1. Open Photoshop.
2. From the Select menu, choose Select and Mask.
3. Under View Mode, unfold the View list.
4. To get a smooth refined edge, find and use the Refine Edge Brush Tool.
5. Create a selection around the object you want to remove from the background.
6. Remove the background.
7. Open Select & Mask.
8. Smooth the selection.
9. Feather the selection/mask.
10. Adjust the contrast.
11. Shift the selection edge.
12. Exit Select and Mask.

Alternatively, you can use a combination of the Contract and Feather tools to smooth jagged edges in Photoshop .