|In the PSP menu bar, select File and Preferences from the drop-down menu. Then, select General. This will open the General Preferences Control Box.|
|From the General tab, select the check-box next to the Anti-Alias Selected Area Operations.||
The anti-alias effect softens the jagged edges of selected areas. Notice the difference between the same selection with and without the anti-alias effect.
The Anti-Alias effect only works in 16 million colour mode.