How to make UI look cleaner?

[Budtup]

Hey, so recently I uploaded a gui-button to roblox.
Here it is:

But I noticed and if you look carefully, there is a rough white outline on the edges of it, this is not in the original image, so I was wondering if you can give me any tips to make my UI look more clean and nice (Perferably image buttons/labels)

Also, I used paint dot net software to make it.

[Wrathsong]

PixelFix has solved this problem for me

Pixelfix: Remove the black edges on scaled images

Pixelfix [Pixelfix-1] Pixelfix changes the color of transparent pixels to match the color of the nearest non-transparent pixel. Transparent pixels stay transparent, but when resized and blended with non-transparent pixels they won’t cause dark borders. How it works Here are screenshots of images in Roblox that have been scaled down, showing with/without Pixelfix and with/without transparency: [Pixelfix-2] Since the transparent pixels are no longer black, they no longer make edges of the im…