The basics of creating a tube or similar surface is to use the EP/CP Curve tool to make the basic shape of your curve that the tube is to take, in the Top/Side/Front views.

Then create a NURBS circle at the required size and extrude it makin sure you select the "along path" option. You will probably have to change settings inthere to get it to look correct. This is the recommened way of dealing with that type of geometry, and is fairly easy to deal with.

Once your 110% happy delete History on it and delete the curve and circle