At least contribute to your 401k to get the full match from your employer if offered. More if you can afford it. Time in the market is huge. Make a budget, have emergency savings. There’s little point in investing if an emergency happens and you have to withdraw your retirement at a potential loss, and that’s before penalties and tax. Take care of your body, especially joints. Be even a little bit active regularly. Figure out a decently healthy diet. These will help prevent health issues which can be expensive. Plus you might look better and feel better too.

All of this sound like too much? Pick one or two and try doing them consistently even if it’s half assed. Half assing something consistently for a long time is much, much better than putting in a ton of effort, burning out, and returning to old patterns. It’s a marathon, not a sprint.

Sorry I know that kinda veered into fitness but I see a lot of parallels in personal finance and fitness/nutrition. Both involve budgets and benefit from a plan and spreadsheets.