I've had my cockatiel for about 8 years now and she only uses her cage to sleep. I put her in the cage at night and first thing in the morning she let's herself out. She's not a cage bird. She's all over the place. Mostly on top of curtain rods, computer monitor, closet. She goes where-ever she wants. I can't just keep her cooped up in a cage.

My question is, she uses the bathroom everywhere and is it possible to potty train an 8 year old bird? She will fly over to her cage and let herself in the cage when she wants to eat something or get some water, but she doesn't use her cage all that often. But she is extremely tame. Always flies over to me and let's me pick her up, pet her, sleeps on me. But I just want her to be potty trained. She's ruining my curtains! haha. Please help me out
David
You may want to try buying or making a gym for her to perch on whenever she is not in her cage. I made one out of a huge grapevine wreath I bought at Hobby Lobby. I washed and sanitized the wood thorougly, then I intersected the wood in order to use three small bowls, inserted in the areas I made and she can forage right there on her perch. She is never in her cage when I'm home, and she is put in the cage for 10-12 hours each night.
Once you get her used to having a territory which doesn't include curtains, etc...make a fuss each time she makes a poop. Then step her up and hold her over a basket or piece of paper and what we did was to say "go poop" until she associated the command and the action. I have to say this whole process took literally minutes. My bird was a toddler when I trained her, but birds can always be trained. You have to be a lot more restrictive because she can get into trouble when flying all over the place. Until she adjusts to the day gym you may have to get her feathers cut. I cut my birds feathers myself, but if you are not comfortable, a vet can do it in two minutes.

That's what I did.
I've had my cockatiel for about 8 years now and she only uses her cage to sleep. I put her ... me. But I just want her to be potty trained. She's ruining my curtains! haha. Please help me out David

I once read an article by an expert of some sort who said that birds have no control over their . . . bodily functions.

Not true. When a bird goes on my windshield I think he aimed for it.

My sun conure trained himself. He has a trash can next to the cage, and he turns around and drops it in the can. "Good Bird!" I can trust him 100% to get it right. He never goes on my or the furniture.

I've learned that positive reinforcement works with both people and my sun conure.
I'd place a trash can right up against the cage and see if your bird can figure it out. Then reward behavior you wish to reinforce.

I'd trim her wings, also.
My bird has a lot of climbing things and places to go to. Birds can get hurt flying inside a house.
I don't think trimming her wings is a route I want to take. I used to clip my birds wings a long time ago, but now she is confined in one room and it's her freedom to fly around the room. She's been here for years and I don't think there's any way for her to get hurt inside of her room. But the only problem is her relieving herself on everything! lol. I really want to do this without having to strip away her freedoms. She'd be miserable with her wings cut.
I don't think trimming her wings is a route I want to take. I used to clip my birds wings ... I really want to do this without having to strip away her freedoms. She'd be miserable with her wings cut.

Okay, I understand that, but I sais to restrict her slowly over time till she thinks it was her idea. I don't change anything in Mika's routine unless I do it gradually. Birds are indeed very sensitive, or at least mine is. One time I switched her seed cup with her pellet cup and she was so depressed I brought her to the vet. The vet told me to put the bowls back and see. She immediately reanimated!

They are very smart creatures.
I don't think trimming her wings is a route I ... away her freedoms. She'd be miserable with her wings cut.

Okay, I understand that, but I sais to restrict her slowly over time till she thinks it was her idea. ... vet. The vet told me to put the bowls back and see. She immediately reanimated! They are very smart creatures.

Every time I move it takes 3 months for my bird to adjust. He does not like changes.
As to the question of "How do I get my bird to stop crapping on the curtains?" I'd like to offer this solution:
Don't let him stand on the curtain rod.
Seems so simple to me . . .
My bird was allowed to fly around the room at one time, but I stopped it after a few problems. Among them was your problem.

My bird became more friendly, social, after I started to trim his wings. He seems to be happier. Less "wild" if you know what I mean.

Height is very important to a bird. This is something to manipulate. This may be your problem.