* Shopping — Don't shop, except for the necessities (and when you need them, buy in bulk). I generally feel like having stuff adds stress to my life. My girlfriend and I once had a somewhat humorous argument over whether a kitchen table is really a "need".
* House maintenance — I'll probably rent apartments as long as I can get away with it, but because all of the best high schools are usually in the suburbs, I imagine I'll need a house once I have kids. It will be a small house, but well built. Poured from concrete so I don't have to worry about weather and tornados (most American houses are made from cheap wood). No wallpaper — that stuff gums up all of the time and is a pain to clean. No carpet or wood — carpet is a grime magnet and wood gets scuffed up. I'll use large tiles on my floors (or at least those ceramic tiles that look like wood). I'll have a tiny yard. If I have to mow, I don't want it to take more than five minutes.
* Commuting — After the initial years of my career, I want a job that requires a commute no longer than 10-15 minutes. Living near a city center or finding a remote job are both solutions to this. My brother-in-law drives 3 hours a day for his job; I can't imagine giving away that much of my time.
The key to having more time is to try to think about how every decision you make might cost time in the future. Granted, many people may not be able to make free time because of circumstances beyond their control, but I think these tips and this kind of thought process can at least help a little bit.