The first step you need to take is to setup Visual Studio to use the Git Provider. To do this you need to go to Tools -> Options and select the Git service provider.
Then select the Open from Source Control option then under Local Git Repositories choose the Clone option and fill in your git settings for BitBucket.
Now the url for the BitBucket repository can be reached by going to the web page for the repository and pulling up the Clone window. You will need to get rid of the Git clone text before the url.
After that you will need to hit the clone button and you will be asked for your BitBucket userid and password. After you enter that in the repository will start downloading.
At this point all you need to do is open up the solution and start working on the project.
You may also want to download some 3rd party Git command prompt tools at this point since the Git provider in Visual Studio does have some control limitations.