Save the raise/bonus/tax refund.
If you are lucky enough to have a job that still gives raises and/or bonuses, save them.
If your pre-raise salary is enough to make ends meet, save the extra you get each month from your raise. Have it automatically transferred each pay-period into a retirement account or savings account.
Get an annual bonus? Put it into a retirement or other savings account.
Large tax refund? Bank it. Then adjust your withholding so you break even at tax time the following year.