Lee in Richmond

I have searched online for how to make this happen, but I am either too impatient, or. . . I finished a simple tube quilting pattern of table runner, but it seems to have a few "waves" when it lays on the table. I thought it just needed ironing, or hanging from one end with no folds, but nothing has worked so far.

Any ideas? Is it maybe getting it really damp and then drying?