Venetian blinds come in many sizes and materials. You can buy off the shelf blinds and customize the fit quite easily. The width of the blind is crucial, usually installed inside the window frame. The length must be longer than the window you are covering. You always adjust the length the same way. Tools you will need are a pair of scissors and a level.

Hang Your Blinds

The first step to a proper adjustment is hanging the blinds. Expand the blinds to the maximum length. This will allow you to see how many slats to remove. You will want the bottom rail to graze the windowsill.

Disassemble the Blind

After expanding the blinds, mark the desired length. A good way to do this is to put a notation on the slat below the new bottom slat. Turn the bottom rail of the blind over and remove the cord retainer buttons. While the blind is still at the maximum length, remove the bottom rail and slats to the desired length. Do not pull the cord that raises/lowers the blinds. This will pull the strings out of the slats.

Alter the Length

Now that you have removed the unwanted slats, cut the excess string brackets and the drawstring leaving enough to put the bottom rail back on. You may want to mark the strings where the knots should be so you are sure the bottom of the blind is level.

Re-assemble the Blind

Once you have the length adjusted, pull the drawstring and the slat strings through the holes in the bottom rail. Tie your knots where you marked the strings. The marks will not be visible. Push all the excess slat string into the bottom bracket. Replace the cord retainer buttons.

Final Adjustments

The drawstrings may require a final adjustment once you reassemble the blind. You can shorten these by pushing the cord tassels to expose the knot. Again, mark the length you want. Cut the cord and tie the knot at the marking. Do this to all the drawstrings so they are even. This will ensure the blind raises evenly. Be sure to save a few slats for future repairs.