Mapper:

Provide all the files of your map in a zip file, make sure that your level is located in the zip root in this way:

Assuming your map is named TC_SandBlasted that would be:

Multiplayer/TC/TC_SandBlasted

Also make sure that none of your directories contains files of zero size, otherwise extraction will fail on the client.

Server:

Add a variable definition to your levelrotation.xml of your server, like this:

 <level name="Multiplayer/TC/TC_Urban_Jungle" gameRules="TerrainControl">
    <setting setting="g_timelimit 9999" />
    <setting setting="g_fraglimit 0" />
    <setting setting="g_pp_scale_income 1" />
    <setting setting="g_revivetime 5" />
    <setting setting="g_roundlimit 0" />
    <setting setting="g_preroundtime 0" />
    <setting setting="net_mapDownloadURL http://78.46.173.173/TC_Urban_Jungle.zip"/>
  </level>

The provided link in net_mapDownloadURL must point to a HTTP URL, HTTPS does not work. Redirects are an option however.
