So...u have to buy some Velcro - one white and one black!
Combine them...
Stick up the white velcro with double-sided duct tape to the wall...
U have to sew the black velcro to the curtain...
And u r ready...without nails, ledges, hammers, drills etc. ...
This is a very cheap idea...try this...if u love to sleep in the dark...