Do _NOT_ under any circumstances give in and go down to reassure your puppy when she starts crying. If you do, you're on a hiding to nothing
In theory correct, in reality ... trying to sleep with a dog howling and barking and whining... neighbours trying to sleep with a dog howling and barking and whining...
Like the controlled crying technique with children, it's a gradual process. Yes, don't go and reassure immediately, but in the end you have to do it.
We had to start with ours in the bedroom and gradually move her further and further away, week by week! Took a good few months before the whining stopped, but she happily sleeps downstairs now.
We didn't have ours from a small puppy, so you should find it a little easier
[typed before the site went down, so may have already been answered!]