Step 1: Card Slots
Now, take a credit card, and rap it with duct-tape so the sticky side faces out.
Repeat this step about four to five times.

PDF Downloads
As a Pro member, you will gain access to download any Instructable in the PDF format.
You also have the ability to customize your PDF download.
The term "duck tape" stems from the initial use of this tape, in the Navy, where it was called so due to its effective water repelling properties, much like a ducks feathers.
The term "duct tape" stems from its later commercial uses, where it was quite often used in venting and ducts, because it seals effectively.
It is considered acceptable to use either form, but quite idiotic to try and claim that one is more right than the other.
To others below me, there may well be a brand called "Duck Tape", but that is not where the name comes from.
(We can further confirm our friend's ignorance in the comment reply below.)
Oh my god, who, the h*ll, cares?!
THAT IS INHUMANE!!!!!!!!!
PS I luv duct tape!