Some discussion about distorting the negative itself and distorting your print within the dark room.
Two Types of Negative Distortions:
Negative burning. This is pretty straightforward.
What you'll need:
A negative and a heat source.
So, if you haven't figured it out at this point, just take the negative and the heat source and apply the flame/ heat to the negative. This will cause the negative to begin become more malleable.
Something to try:
Using an indirect or low-heat heat source may permit a more controlled distortion of the negative such as stretching and what not.
Example:
Through the MeadowThe way the negative has bent in on itself was achieved through burning the negative.
Negative scratching.
Scratching the negative is something you typically try to avoid in film photography. The only thing to remember is you need an incredibly small point. Using something like scissors or a knife might be too wide of a point to use.
Depending on the size of the negative (35mm versus 120-film) you can control the scratching to a greater extent.
Example:
Back to SchoolIf you're interested I will continue this thread on distortion techniques.