I have a 4 mth old lab and I'm trying to calm her down how do I calm her down

When she gets overly excited ignore her.

That is usually the best way to calm a dog down because they crave your attention and when they realise that acting hyper is not going to make you pet them they will eventually learn to calm down.

Unfortunately you did not pick the best breed if you wanted a calmer dog. Labs are known for being neurotic and hyper.

All labs are a little more hyper when they are puppies. I have a lab-retriever (whew) and he's 3, he hasn't calmed down a whole lot but there is a difference, anyway my piont is that its going to be very hard to train you dog, you just got to show her that what she's doing is not OK by saying no or tapping her nose firmly with your fingers or both works just as well together.

Exercise! :)

You've already received some good advice here.

Ignore attention seeking bad behaviors such as jumping up.

Other then that your dog is an energetic breed and a puppy at that. The puppy needs plenty of exercise to help shed off that excess energy as well as things to keep her entertained and focused. Does your dog enjoy fetch? As a Labrador Retriever they generally are very good at retrieving. I've met very few labs that didn't adore fetching. This simple task may help keep your puppy focused and help her wind down without requiring you to do too much yourself.