As
you may have seen the old .pak system has been
replaced by .pk3 files which makes it easier for
users to distribute their work.
You can open up the .pk3 files in winzip as well as
use it to create your own.
Once
your map is complete and your ready for the world to
see you need to get the setup right first.
As
you can see from this shot each item has it's own
place to live

levelshots
- yourmap.jpg
maps - yourmap.bsp, yourmap.aas
sound\world - any ambient sounds you've created and
are using
scripts - custom shader files
textures\yourtextures - any new textures you've
created
when
you add these folders and files to the zip file
don't include the root directory, i.e qw3level, have
it so it looks like this

it's
a good idea to keep the .bsp filename the same as
the .pk3 file
yourmap.bsp - yourmap.pk3
the level shot should also be the same name as your
.bsp and in .jpg format.
Once
you've got your .zip file built up we need to rename
it so it has the .pk3 extension.
an easy way to do it is to go into windows explorer
and go to view>folder options>view and then
uncheck "hide file extensions for known file
types"
then click on your .zip file, right click and go to
rename and then change the .zip to a .pk3