Question about .zip files

I checked the memories for something like this, but I could find anything.

I have just started making textures, and was hoping to post them in a community so that others could use them as well.

I have never created .zip files with WinZip, and I am totally lost. To see what I am trying to accomplish, you can look at communities such as 100x100_brushes.

Does anyone have a tutorial on how to create .zip files and post them on a community such as icon_textures ?

Help would be greaty appreciated.
-Emma