Can I use Cinccino's "Make Do" Ability if there are no cards in my deck, just to discard a card?
No, you can't use Make Do if there aren't any cards left in your deck.



x2Make Do
You must discard a card from your hand in order to use this Ability. Once during your turn, you may draw 2 cards.
Energy AssistAttach a basic Energy card from your discard pile to 1 of your Benched Pokémon.
Its body secretes oil that this Pokémon spreads over its nest as a coating to protect it from dust. Cinccino won’t tolerate even a speck of the stuff.
Can I use Cinccino's "Make Do" Ability if there are no cards in my deck, just to discard a card?
No, you can't use Make Do if there aren't any cards left in your deck.
Can I use Cinccino's "Make Do" Ability to discard a card, then do other game actions such as play a Cynthia, and then finally draw the two cards later in my turn?
That's not how it works. You have to perform all of the actions of the Ability before moving on to other game actions.
For Cinccino's "Make Do" Ability, can I use it when I'm discarding a card as part of some action or effect?
No. Discarding a card from your hand is part of the cost of using the Ability. You can't use a discard done from some other effect or game action.