Joining lines into a polygon

[Birdseye42]

If I have, say, five separate 'pen' lines which join into the shape of a polygon, how do I convert them into a polygon so that I can fill that polygon with colour?

[PixelPest]

Select all lines and when Node-tool is active click "Join Curves" should do.

Cheers

[Birdseye42]

Thank you.  Going through a learning curve - brilliant software.