Try to keep your health above 2 at all times, as Miusaki cannot die at 3 HP or higher. Home's healing is a big aid in this as well as cards.
Saki's Cookie is an excellent card on Miusaki because it can bring her from 2 to 3 HP, meaning her passive guarantees survival. Other healing such as Dinner can also be helpful however tend to help other players more than Saki's Cookie would.
Quick Restoration is extremely useful on Miusaki. Assuming she is at least 3 HP, it lets her take a hit completely risk free as she will heal back to safe HP immediately.
Portable Pudding is a similarly strong battle card, bringing Miusaki back to safe HP if she finds herself in a dangerous battle with 2 or less HP.
Lucky Sevens is a very good card on Miusaki because she generally will not care if she rolls 0 on defense due to her passive, but appreciates the possibility of a 7. On the flip side, she will not care if her opponents roll high on ATK against her but loves if they roll 0.
Despite benefitting from cards, Miusaki can still be an effective card control user with Gift Exchange. Her passive is very strong simply due to making fights redundant and even in the event Gift Exchange is used, she is likely to still have cards that help her.