I would suggest crate training.
First thing in the morning you take her out of the crate to potty outside.
Tell her "go potty" or something similar each time as she will eventually be able to recognize this command and it will be very helpful for the future.
Only keep her out there 10 minutes. Any longer and they forget what they are out there for which doesn't do well for the training.
If she doesn't potty, put her back in her crate. Try again in 5-10 minutes. Keep doing this until she goes. It takes time but they learn to understand and it works.
When she does go give her a lot of praise and some treats, make a big deal out of it. Yorkies want to please you and this will encourage her training.
Until she is completely trained, anytime she is inside the house and you can't supervise her 100%, either put her in a crate or pen. This will really cut down on her having accidents.
If she is having an accident in front of you, simply tell her no, pick her up and take her outside. Don't scold her for having an accident or she will simply be afraid and will just make sure you aren't in site when she has an accident. If she manages to go some outside, praise and reward her.
Keep a good feeding and water schedule and this will help the training process as she will develop routine bathroom habits. After all if you know when she is eating and drinking, you will know she will have to go shortly afterwards.
Have a regular potty schedule so she knows when she will have the chance to relieve her self making her more likely to hold it then if she doesn't have a regular schedule and she goes anytime she wants.
Please don't give up on her yet. Yorkies are quite known for being difficult to potty train. They take longer than most breeds. It takes a lot of time, consistency, patience, and praise but you will get there and it will all be worth it in the end.
Good luck!!
