You need to export your data from Goodreads first. Please note that you must use their website. The Goodreads mobile app does not support exporting. Here is the process:
When logged into Goodreads, click here.
Click on "Export Library" at the top.
Note: This may take some time depending on the size of your library.
When done, it will allow you to download a CSV file. Download that.
Go to your settings page and scroll down to Goodreads Import. Click the + sign beside it to expand it.
Choose the file on your computer, and then click "Start Import".
If all goes well, you should receive an e-mail confirming the Goodreads Import has begun, and a second e-mail when it is complete and all books on your list are matched.
We have a video we made in Windows showing the process, using Chrome. This will differ slightly of course if you are using a different device, but the general process is the same.
If you run into any issues, don't hesitate to contact us.