I follow an unconventional method that I came up with myself: any time I spend money on anything “unnecessary” (so, excluding things like rent, groceries, etc), I put an equal amount into my savings account.
Pros include: This method alleviates my guilt of spending money on myself. It scales, so the more money I make, the more I tend to save. It’s flexible enough that even during the times where I can’t afford to save, I can still stick to it.