-If you buy a house, don't buy more than you need. (ie: Do you really need a large formal dining room that's only used twice a year, or 3 baths, or huge BR's?) We raised two children in a small, "starter size" home. We did this by utilizing space wisely, and it worked out fine. We bunked the kids in one BR, and I think they are closer today thanks to that rather than being able to isolate themselves in their own BR's.
Another big benefit of a smaller home: Now, unlike many other empty-nesters, we don't have a big home to sell and downsize back to a "starter-size" home! This is a big savings in cost and convenience, as well as the savings over the years from lower utilities/tax/upkeep on a smaller home.
-"10 year rule" on cars -keep them at least that long.
-Because the car will be worth <$500 when sold, don't pay the large cost to fix minor collision damage that will be irrelevant by then. My wife had one car that I think she managed to dent every piece of sheet metal on (no other cars involved). Just minor damage, but would have cost many thousands to fix all those dings and if every incident was reported we wouldn't still have good insurance rates.
-I love performance cars, but since a young man have forced myself to drive econoboxes. Cars eat up more income than many people realize. It's a personal decision, but always buying only the car you need instead of the slick car you want is one of the easiest and best ways to save and be frugal.
-I've cut my own hair (buzz short) for >30 years, and had done oil changes on two cars nearly as long before retiring from that a few yrs ago. Over time, that's a lot of savings.
-Use coupons at the grocery store. The Sunday paper pays for itself, and lots more.
-Shop the sales at stores that sell at bargain prices, not the stores that sell a "name".
-Never hire anyone to do something you can figure out and do yourself, or have resources/help to get done. This especially applies to home remodeling/renovation. Within the first 10yr in our home, I redid our kitchen, two baths, family room, landscaping, and added a large screened-in porch at a small fraction of what contractors would cost. Don't underestimate what you can do yourself with some good research, planning, and resourcefulness. If not experienced, find family or friends who are handy and offer to help them with their own projects. You will learn, and then also normally get help with your own.
-A great family vacation does not have to be expensive. Camping, hiking, canoeing are inexpensive and great ways to bond and enjoy memorable times with your children. I'm not a fan of DisneyWorld-type vacations, but to each their own.
-Be an engaged parent: beginning with preschool, always impress upon your children the importance of education and doing their best. The benefit it two-fold: you raise the potential that your children will be happy and successful, and also raise the potential that if college-bound they will receive college scholarships that can greatly reduce that financial burden. Even without scholarship savings, doing your best to prepare/ensure your children graduate and enter good careers is one of the most frugal things you can do. Teaching them to stand on their own two feet lowers the possibility that they will seek/need financial assistance from you when they should no longer require it.
Better stop here -think I could go on and on...