Hi,
The bend is from the two layers of fabric not being aligned to each other on straight of grain.
If you hold the fabric up and match selvage edges, both sides hanging down will hang straigth, or with slight ripples as you look down the sides. The ripples are the straight of grain being pulled out of whack (off straight alignment).
Holding the fabric up in the air, the selvages together, slide the two layer edges against each other (left or right) until you see the ripples in the sides disappear.
You can now lay the fabric down and press a crease/fold if needed.
You should cut the selvages off at this point and cut a test strip the width you need for your porject, or at least 2-3 inches wide.
Open the cut strip and look at the crease/fold. Does the strip lay straight from end to end with now dip or curve in the fold area? If so, you are good to go and your fabric is now folded straight of grain and can be cut for your project. If not, look for smaller ripples and shift layers until they disappear.
Good luck. This is easier to watch than tell!!!