Make sure you run the game at least once before copying over the data.
You can either overwrite of copy the files the over.
If you want to read more about back ups:
http://sims4.crinrict.com/en/2014/09/backups/
http://sims3.crinrict.com/en/2011/03/faq-what-files-should-i-backup.html
Do I need to bring the saved outfits over too? Should I just copy the whole Sims 3 folder and put it in the new saves folder?
You can choose to copy whatever you want, the links describe the files and what they are, so if you feel you need them copy them.
The files need to be the same, old computers: 'Documents\Electronic Arts\The Sims 4' is 'Documents\Electronic Arts\The Sims 4' on the new computer.
So if you put The Sims 3 folder (Documents\Electronic Arts\The Sims 3) over to the new computer it needs to be 'Documents\Electronic Arts\The Sims 3'.
And not 'Documents\Electronic Arts\The Sims 3\Saves'. Make sure if you copy the entire 'The Sims 3' folder over you overwrite the newer one, or if you want to keep the newer folder to rename that.
For the folder (all you saves etc) you want to use the names and folders should be on the same location as it was on your old computer.
The game doesn't recognize the folder if it's not on the right location or has the wrong name.
Community Manager
