How to share a single dataset with a user
Dataset editors can share dataset with other users. To share a dataset, click on the dataset's name and select Share. If you don't see this option it is likely that you are not an editor of the dataset, and you should contact the dataset's owner to either share the dataset for you, or give you edit privileges to the dataset.
Next select a user and whether they will be an editor or a viewer, and click Share.