For a natural and casual look on your windows, few things work as well as bamboo blinds. These "first apartment" staples are very inexpensive, as well as being a classic design that blends well with many decors. Most bamboo blinds have a cord system built in that facilitates raising and lowering the blind, as well as a method for locking the blind in place once it's been rolled to the top of the window.
Inspect the bottom of your bamboo blind to make sure the bottom edge is even. If you roll up the blind crookedly it won't secure well with the cord.
Straighten your blind if the bottom is crooked. Roll the bottom of the blind up by hand about 8 inches. Grasp the roll with both hands. Twist the roll by turning it toward you on the side where the bottom is shorter, and away from you on the side in which the bottom is longer. Allow the blind to unroll naturally.
Grasp the blind cord and move the bottom of the cord to the left toward the center of the blind. Keep pressure on the cord without pulling it until the cord end is near the center of the blind. Pull on the cord until the blind rolls up as much as you desire.
Pull the end of the blind cord to the right, away from the center of the blind and out toward the side. Keep the pressure taut on the cord while moving it. Pulling the cord end to the right locks the cord in place, tying up the shade in a roll.