This is really a multi-faceted question, and you need to consider the reason you are considering going into debt. Debt is slavery, so the decision shouldn't be taken lightly.
Credit card debt - the interest rates are enormous, so you should always clear your balance when the payment is due. If you are unable to do this, then you need to take steps to reduce your expenditure or increase your income.
Speculation - This one is a bit harder, and I've used short term loans to make money. You need to watch the interest if any, and you need to be able to cover any losses if they happen. Examples are - running a business with a 30 day credit line, and using the credit to supply corporations. You need to monitor this very closely to make sure you don't build a problem. Another example is buying a car for repair, and selling it quickly for a substantial profit.
Your house - You should be able to negotiate a very low interest rate for this type of loan, and it can make sense if the repayments including interest are less than you would pay for rental.
Fripperies - if you can't pay cash for them, then do without.
Food and daily expenses - never use debt to pay fer these. If you haven't got the money to buy food, then do something to earn some money, cut somebody's lawn or clean their windows for example. Alternatively,cut down on food purchases. Nettles are very healthy when boiled, and you can probably find them for nothing.
Bitcoin is extremely volatile, and I believe the long term prospect are good. However, you shouldn't buy Bitcoin unless you can afford to tie up the money for at least two years in my opinion.