Alter curtains?

[Chillouttime]

i have some lined curtains that need altering, making shorter and adding a blackout lining. What’s the easier way to do this please. I have a sewing machine and some very basic knowledge.

What type of curtains are they? If they have header tape you should able to untie it and smother them back out. Ideally you would remove the tape, position the blackout material so it is 1inch narrower and shorter than the curtain all the way round and sewn it down the sides when the material is good face to face then turn it around and iron the sides smooth. Then put the tape back across the top and see that back in place across the top of both the curtain and blackout material. If the blackout material will fray then you should turn that up and tack it (don't sew through the curtain material). Otherwise you can get iron on hemming tape

Thanks @redastherose they are pencil pleat curtains with a lining. Yes they have header tape at the top so sounds like I need to unpick that and take it off and then add the blackout lining.

You can just hook a black out lining in if you don't need them to be attached.

Like this

If you want to do it properly you basically have to remake them. If you want an easy fix you can just add the blackout blind to the back as a pp said.