If classic version (… 2009) then you do this directly from the object designer in the client (Finsql.exe or fin.exe). If post 2009, then from the report designer in the development environment, but here using either Visual Studio (RDLC) or SQL report designer.
Then you need to use Visual Studio for this. From within the NAV report designer open the “Layout”.
Then from within here you can just move the fields around as you like.