(1) When you conduct your normal draw during your Draw Phase: You can reveal 1 of those drawn cards; place it on the bottom of the Deck, and if you do, draw 1 card.
(2) When you draw a card(s) by card effect: You can reveal 1 of those drawn cards; send this card to the GY, and if you do, place the revealed card on the bottom of the Deck, and if you do that, draw 1 card.