You may also choose to sign up with Facebook or LinkedIn.
Note especially the instructions for password selection.
Go to Collect and then Import References.
Next to Import Option, choose Select Favorites.
From the box on the left, choose RefMan RIS (RefMan stands for Reference Manager. RIS is the file format that is most common for citation files.)
Choose Copy to Favorites. You can choose other favorites here too if you frequently upload citation files exported from other sources on this list, but RefMan will cover most of them.
Then Hide the box.