This. That's the most reliable way to improve one's odds of winning something. But at a high cost of entry. If doing this, consider adding Power Play for $1 more per ticket - adds $35 more, raising cost to $105, but improves the payback percentage somewhat.
Another strategy is to buy multiple tickets and choose diverse numbers on them - have few, if any repeating numbers across tickets. That way, it's highly likely at least one ticket will win something. However, regardless of strategy for Powerball, the overall payout percentage remains the same...
The overall payback percentage for Powerball is 50%, but depending on how one plays and one's objectives, the overall payback percentage could be less or more...
The simplest way to get improved overall backback, as in well over 50%, on Powerball is to mainly play and/or buy more tickets only when the jackpot is very large, but that comes with an important caveat - it assumes one will hit the jackpot. Not likely, but it could happen. Otherwise, the effective overall payback percentage is far lower. The mathematical payback percentage ~50% (including hitting jackpot) and effective payback percentage (probably under 40% excluding jackpot prize) can be very different. On an aside, some casinos offer 99%, or even 100%+ payback slots, and yet still make money, because the top tier prize(s) are so difficult to hit that most players give up long before then, and shift their play to lower payback games.
In my view, if one seeks to win anything meaningful from the lottery, they do better with pick 3, pick 4, and various pick 5 games, such as PA Quinto (5 separate digits), PA Treasure Hunt (5/30), and PA Cash 5 (5/43) games. The top prizes are, relatively speaking, for those games within reach. For example, if one plays one PA Cash 5 ticket everyday for 5 years (~$1825), the overall odds of winning the jackpot is 1 in 527.
If one seeks to improve their overall odds of winning anything, choose games with better payout percentages, such as Cash4Life (55%), and some other select numbers games with better than 50% overall payout. Instant tickets tend to be in the 65%-75% range, though some vary from low as high 50s (worse than 1 in 5 odds) to in excess of 80% (better than 1 in 3 odds) - it's no wonder instant tickets are now far more popular than numbers games.