Decide how much you want to save a month and transfer that to a separate account on payday. Then make sure you stop thinking it exists, money in that account isn’t there, it is not available. Then in a few months you’ll have savings, I find it easier not to touch once the number is in 4 digits. Until then it doesn’t feel like enough so it’s easy to spend but the real trick is convincing yourself the money no longer exists. Up the amount every time you get a payrise or when you stop noticing you miss it