In order to attach lines together, you have to select a line from H and then go to modify > Geometry > Attach.

Detach is at the bottom of the Geometry.




Create > lines ( Smooth : creation method) > draw sides > Modify : Lathe

OR

You can draw a line and go to modify > spline > outline. :D




To Turn ON/OFF grid : Press G
Snap Toggle ( Make Straight lines) : Hold on to shift.
Make Outline : Modify > Line > Spline > Select Outline > Drag



Make Lines and the modify them, go to sub and choose spline > modify the outline at the command panel (maybe 10 to make walls) > extrude




Select the lines and make sure there are no double lines because the whole thing would turn blue instead.
Extrude > Increase/Decrease Perimeters ( to create walls).





Ex : Create a circle > Change it to edible spline ( right click on object) > extrude > click on vertex ( at the modifier) > select a point > right click and choose the function you want.




Add another modify ( Bend) > adjust the perimeter and your object will bend .
To make it more realistic , your have to modify the segment.





Adding Curve + Tapper from modify



Z is for zoom / half