To start with do not punish the cat. She's doing this for what is - to her - a good reason.
If you see her about to go, gently pick her up and put her in the litter box (for this, you're going to want to have litter boxes in easy reach for a while), then praise her for going where she should go. I'd recommend taking a look at the answers for How can I redirect a cat about to pee outside the litter box? for some practical advice. It's important to get the smell of urine out of anything she's hit because otherwise it will be an invitation to her to use that place again.
I'd start by taking her to the vet and ruling out any health issues. There are a number of health problems that can cause cats to become incontinent.
If you've made any major changes lately, you could have a stressed out cat (which will also cause cats to go where they shouldn't).
Some other suggestions are to make sure she has clean litter (some cats are more fastidious about this than others), make sure the type of litter doesn't bother her (some cats can be very fussy about this and refuse to use litter they don't like), make sure there's nothing around that she can use as a substitute box when you're not there to redirect her.
In addition, you're going to want to reassure her that she is still wanted and welcome no matter how frustrating her urination is to you. This is particularly important if she's doing this because she's stressed: the safer she feels the less likely she'll go where she shouldn't.
Finally, use a black light/uv light to find where she's urinated, and clean everything with the best quality urine odor killers you can get (I'm not going to point to products here because what's available varies depending on where you are - ask your vet or the local pet supply store what's best for cleaning hard floors, carpet, and fabrics).