This can be done in the Holdings tab in your Portfolio.
Just click "Add Lot" to input amount of shares, share price, date and transaction type.
If you are on a mobile device or tablet, tilt the device to the wide view in order to bring up the extended portfolio menu, and then select holdings.
Please email us at subscriptions@seekingalpha.com or give us a call at 1-347-509-6837 if you need any help.
If you haven't subscribed to Premium yet, you can unlock access to our subscriber-only features by signing up here.