I just found out that my parents signed me up for the next administration of the ACT, and I don't have much time to study for it between my classes and other commitments. I already got a very high score on the SAT, and I've heard that the ACT is easier. Will I be ok just winging it? I'm aiming for a score of 30+.
Getting a high score on the SAT doesn't guarantee that you'll do just as well on the ACT, especially if you studied extensively for the SAT. The two tests are formatted differently, so you could be thrown off by the new challenges presented to you on the ACT (the ACT involves more time pressure, and the Math section is slightly more difficult). The ACT isn't objectively "easier" based on average scores. If it was, colleges wouldn't universally accept it as a substitute for the SAT!
Still, if you already did well on the SAT, you might be fine without studying. I'd say you should just take one timed ACT practice test and see how you do. Depending on your scores, you can decide whether or not you want to spend more time on it. Even if the ACT doesn't go as well as you're hoping, you'll still have your high SAT score to fall back on, so the stakes aren't super high. There's no need to stress yourself out with excessive preparation.