How do I make walls?

I just got Gmod, and I seriously SUCK

How do I make walls?

Spawn a few props, freeze them, use easy weld, match up the ‘ghost figure’ of the prop, then repeat.

Uh, way to make his brain asplode.

UM WAT LOL

I lost you at ghost figure.

AND I DOWNLOADED AN ADD ON FOR A BUNCH OF WEAPONS, HOW DO I USE THEM?

Thats what I do.

you put the downloaded folder into Steam\steamapps<your steam account name>\garrysmod\garrysmod\addons\

I use doormod with disabled blast doors.

Spawn 1 prop.
Pick it up with the physgun.
Hold down E.
Rotate it so that it is standing up.
Right click and left click at the same time, then quickly let go of both keys (to freeze it)
It is now standing up. It is a wall.
Congratulations.

To make a really long wall, get the stacker tool: http://www.garrysmod.org/downloads/?a=view&id=29854