How can I make existing icons flat? I tried to find any tutorial about this, but there is almost none. Is there anyone that knows about this stuff?
There are no automated tools that could do this (well).
There are a couple simple ways to this:
- Replace existing colors with solid flat colors and subtle gradients (see example below)
- Redraw/-create the icon in flat design (see icon below)
Here, for example, the helmet is black, so you can select the outlines of the helmet and replace the gradient with a solid black color. After that you can optionally add a simple (gradient for the) "glow" effect.