How can I make sure Satan doesn't put me in financial debt during the religious holiday season?

By spending the days in a desert for 40 days and 44 nights.

Satan does not control your spending, you need to put the wallet in your wife's purse...Oops that would be bad, wouldn't it?

It would certainly help to recite at least 15 decades of the angelic psalter of the Blessed Virgin daily and with care.

Stop being a slave to traditions of men.

(John 8:31, 32) Then Jesus went on to say to the Jews who had believed him: “If you remain in my word, you are really my disciples, 32 and you will know the truth, and the truth will set you free.”

Seems like you would be in a better position to do that than Satan.

Don't go out and buy a bunch of things.

Satan isn't using your credit cards, you are.

Use self control.

Galatians 5:23

...gentleness and SELF-CONTROL. Against such things there is no law.

Don't spend any money. That way you can be pretty sure.

Lock you credit cvards in a safety deposit box