Ways I've wasted my money I regret a lot
1. Not saving/investing 10% of my income
If I'd done this I wouldn't still be working past retirement age. Whatever that 10% was spent on, in the long run, was a waste.
2. Wine, women and song
Once I started drinking I couldn't moderate. Took me a long time and a lot of hard-earned cash to learn to not start.
3. Buying things instead of experiences
The things usually end up stored in the garage. Experiences are what life is made of.
4. Cheap things that never last
Especially when it comes to tools and equipment that could last a lifetime.