How do you organize/name your icons?

Hi,

I don't know if this topic is okay here, i hope so. I wanted to ask you: how do you organize your selfmade icons?

- Do you have special filenames?
- Do you save them all in one folder or do you sort them in categories?
- Which format do you choose?

Many questions, but i find that interesting. I don't really know how to organize mines, so i would be happy to get some tips of you!