If you aren't landing the Waft, then you aren't playing Wario as intended. It's probably the most important attack in his entire moveset.
Here are some of the ways I generally land it besides as an edgeguard:
- Jump at an opponent falling above you and chase them mid air. The natural reaction to someone jumping at them is to air dodge, chase that air dodge and waft the moment it ends for a Waft punish.
- Roll happy opponents who roll into you are susceptible to the Waft. Requires a good read though, you have to know they're about to roll or just have really good reflexes. Only consistently works on bad players though.
- Opponents who jump off a ledge and the go back on lose invincibility. The second they're back on, Waft them (or dsmash them if you have no charge or can kill them anyways).
- If you know a dash grab is coming, spot dodge and immediately Waft. If you're fighting Link, Robin, ZSS or other laggy grabbers you can punish their standing grabs too.
- Punish dash attacks, aerials, or anything with that leaves the opponent momentarily vulnerable but close. The trick is to never overestimate your range, but always be thinking about landing the waft. The second 1 minute ticks by, always be prepared to punish with it.
- Force an opponent to air dodge close to the ground with a fair and punish their landing with the waft.
Remember, it is VERY important that you land this move. Getting the first kill as Wario often leads to taking the entire match if you're careful. Due to his small size and high weight, Wario is one of the hardest characters in the game to KO, so if you get that early Waft lead, it can be curtains for your opponent.