Or, right click (or control+click) and select ‘Creative Archive of …’. That’s it.

Dan, try uploading that to a webserver and extracting the file; It usually makes a mess.

[...] couldn’t be much easier. I’d previously posted command line instructions, but it turns out that there’s a huge number of people who don’t know the easy way: [...]

Or use:

> zip {target file} *

and the target file will be appended with “.zip”