How can you prove a mom un fit if she doesn't work, have her own place, and just hangs out with her friends? i'm trying to get custody of my daughter but, everyone said women always get the kid.

Women do not always get the kid, I've known a couple of single fathers that ended up with custody simply because the mother was so horrible. However, the reality is you will be facing an uphill battle, the courts do tend to favor the mother. If you can prove she doesn't work, doesn't have her own place, and just hangs out with her friends and this is all having a detrimental effect on the kids you may have a chance.

You don't. You put together evidence as a whole, and present it to the Judge. Why not go for joint physical or bird nest custody?

http://tinyurl.com/JointCustodyMaking-A-Case
http://tinyurl.com/BirdNestCustody2
http://tinyurl.com/Custody-Can-A-Father-Win

You'd be better off trying to find some type of evidence that she's abusing or neglecting the child. Being unemployed or having friends doesn't mean she's an unfit mother. If your child is old enough, it would be better if you could talk with her and see if she would even want to live with you, primarily. If she doesn't want to leave her mom, she may feel the stress (extremely) of protecting her mother, no matter what, and eventually resent you for what you're doing to her and her mom, even if you're doing what you are doing because you want what's best for your daughter.

I would try to have your daughter at your house more and try to work it out with your daughter's mother by offering to help her out by taking in the daughter as often as you can. No mother wants to "feel" like she's unfit (especially publicly) so she may put up a fight. If this is about what's best for your daughter, I would try to stay out of court as much as possible and instead, try to make it seem more understanding of the mom and you want to help her situation with raising your daughter.