Hello! I'm giving a very short tutorial on how to make an icono square (since I often saw many un-square icons). tu don't need Photoshop o GIMP o heavy picture editors. Here I'm using link
1. Click "Editor". Here you'll see a Photoshop-like layout.
2. Click "Open image from computer". Select your icono o any picture tu want to make square.
3. Click on the "Crop" icono on the parte superior, arriba left of the panel. Choose "output size" on the "Constraint" dropdown. Enter 200 x 200 o whatever square size tu want.
4. Drag the ratón over your picture. Hit Enter.
5. Don't forget to save your square picture!