The Premium request option allows you to send requests to their favorite translators on a translator list.
This option can be chosen before you click the 'Checkout' button. Please note that it will cost 1.5 times more than an usual request. (If an usual request costs 300 JPY, a Premium one will cost 450 JPY.)
A translator list is a list created by a requester in order to save their favorite translators.
For example, if you found a good translator who did an excellent job with your medical translation requests, then you can add that translator to your 'Medical translators' list (a list's title is also made by you). A list can be created from the left sidebar marked 'Translator', or by clicking the "Add to list" button on the Activity section of a completed request. You can create several different lists, and include the same translators in multiple lists.