I line dry, back to back, pegs at 4 corners (pegs with grips that don't bite in, plastic not wooden, though not a problem if you trim off).
Then under weights for a day or two if necessary (it isn't always).
Air drying is supposed to be the safest 'archivally'.
The wavy edge lines are usually from handling the prints whilst wet/paper stretching - tends to be more noticeable on larger prints.
With careful handling throughout the process, it can be prevented (don't grip the print in the middle of an edge, but at the corners).