I remember a teacher in school once threatening to have our guts for garters if he caught us doing wrong again. It means, of course, there will be a serious reprisal.
It is apparently British. I read here.
Despite being a long-lived expression there, aided no doubt by the rhythmic alliteration, uses of it aren't found in any great numbers in other countries. It may well have had a literal meaning as it originated in the Middle Ages, when disembowelment was used in the UK for torture and execution. In these more enlightened times the expression is limited to figurative examples like, "I don't want to tell Dad that I've scraped the car - he'll have my guts for garters".
A printed reference to 'guts for garters' appears in Robert Greene's The Scottish Historie of James the Fourth, circa 1592:
Ile make garters of thy guttes, Thou villaine.
Whether that was a literal threat and whether people did actually make garters of the guts of their enemies is open to question. I can find no direct evidence of a documented example of such a practice, but it is certainly quite plausible. Worse things happened; the punishment of being 'hanged, drawn and quartered' was on the statue book in England until as late as 1790.
There are several other instances in the 16th/17th centuries of allusions to the use of someone's guts being made into garters - "Sir, I will garter my hose with your guttes" etc. The earliest use of the actual wording 'guts for garters' that I can find comes quite a long time later, in a piece by William Curry, in The Dublin University Magazine, 1843:
I'll butter my knife in him, and give him his guts for garters.