I use USAA for everything. I have a spending account, a billing account, a savings account, and a mutual fund. I also have TSP (like a 401K). Every month, I pu

I use USAA for everything. I have a spending account, a billing account, a savings account, and a mutual fund. I also have TSP (like a 401K). Every month, I put $600 into my TSP, $1000 into savings, and my total bill amounts into my billing account. The rest goes into my spending account. Whenever I get tempted to buy nonsense, I ask whether I'd rather buy that or put that money in my savings. If I don't really need it, it goes in savings. When savings gets over a certain amount, I transfer a chunk into my mutual fund.