how do i get my cat used to me holding her?

My cat doesn't like it when I hold her in my arms, or carry her,
She tolerates it for a second then wants back down.
If I don't put her down she will squirm, and scratch me, until I let her go.
She doesn't like it when I gently set her on the floor either , she would rather me just let her go, and her fall to the floor.
When I try to put her down on the floor as I do my other cats, she squirms and scratches me. Its obvious whoever had her dident play with her very much, and I'm trying to work on a few things with her.

I need to try and fix this, not only because I want to, but what if there was suddenly an emergency, and I had to grab and run out of the house with her.

Any ideas on how to fix her not liking being held?

How about some positive reinforcement by giving her some yummy treats when she stays in your arms for a while? I like to recommend any type of freeze dried meats you can get from a local independent small pet store, but any tidbits she loves, like maybe some parmesan cheese or other meat-based protein type of snack could work if she's food oriented. I hold my kitty and walk around a bit, and never let her down on her terms. Once she is calm and stays in your arms a bit longer, even an additional second, you can offer her treat and let her down. It'll probably take many practice sessions, but cats tend to learn things much quickly when positive reinforcements are used, and not negative ones.

Keeping her claws properly trimmed also helps prevent those fine, sharp points from digging into your skin. You can also use soft paws, but you'd still need to trim her nails first.

Good luck!

Some cats just don't like being picked up.
I have one like this. She will snuggle in my lap quite happily for hours but she just wiggles and squirms if I try and pick her up. She's just over 4 years old and she has always been like this even though she is and has always been played with.
Sometimes you just have to accept them how they are.
As for emergencies, just make sure you have a carrier stored close by that you could quickly put her into. Or even keep it out for her to nap in if she is ok with it.

I agree, my Chrissy would not allow anyone to hold her long either, she preferred to ride up on my shoulder. I keep my carriers right by the garage entrance door, covered with a sheet, so I could grab them quickly if I would need to. I always figured there is no way to hold a terrified cat if something like a fire was going on. You may want to notice where she goes when she is scared, mine hide in the basement under the bed, it's good to know where are if you are in a hurry during a crisis. Even a cat that loves to be held will fight you if they are scared, so I wouldn't worry too much about 'teaching' her to be held. Just hold her often, but let her go as soon as she is uncomfortable, she has to be taught it is not a bad thing that continues forever like she thinks it does. All the luck!

I agree with the previous posters that this is often a personality trait. The only cat who would let he hold her for more than 2s was Shizu, although she has since passed. The rest vary from immediate rage to mild upset. One of them screams bloody murder until you let ago. Yet, if she likes you, she'll hop on your lap & sit there for hours. The other will rip you to shreds, she wants nothing to do with humans. The rest just squirm & complain. Sorry I can't be much of a help, but we can still love them without holding them!