I don’t have any secrets beyond this: don’t buy crap you don’t need.
The only recurring monthly bills I have are my rent, my electricity, my car insurance, my internet, and a very cheap ($15/mo) cellphone. The only things I spend money on regularly are gas and groceries, and all the groceries are fruits/veggies/bread/raw meat.
I do not regularly spend money on these things: clothes, take out or restaurants, makeup, jewelery, impulse purchases, premade food, Starbucks, fancy rims, a new cellphone, video games, movies, beer, pizza, cable TV, etc.
If you don’t spend the money, it becomes saved. It’s as easy as that. Spend a week recording every single thing you spend money on, then sort it into a few categories and observe where your money is going. Then, you can begin to cut back on things you’re spending too much money on.