How do you attach money to prepaid subscription cards?!

How do you attach money to prepaid subscription cards?

I want to subscribe to a magazine using one of those little cards that they stick between the pages. I put in all the information on the card, and checked off the box that said "Payment Enclosed". On the backside of the card, it says "No postage necessary if mailed in the United States." How do I attach the money to the card?

3 weeks ago
And also, can you pay in cash or must it be check?

Like others have said, you must put it in an envelope and put a stamp on the envelope as well. It's best to mail a check (for security and tracking purposes.) However if you must, and if the magazine company didn't specify that you have to use check, then you should include WELL-CONCEALED cash, so you can't see the cash through the envelope. If I were you, I wouldn't staple the cash to the card.