This is my update of the original "Personal-breath-smeller". This one has pictures. These are the materials that you'll need:
Step 1: What to do if your straw is bendy
If your straw is a bendy straw, simply cut off the bendy part.
Step 2: Cut your straw in half.
Cut your straw in half.
Step 3: First Half
Take your first half. Cut a 45-degree angle off of one of the tips.
Step 4: Second Half
Take the second half. Cut an oval on the side about 2-thirds of the way down.
Step 5: Tape
Tape the 45-degree angle to the oval so that it is all a big tube.
Step 6: Tape 2
Tape the tip of your tube shut.
Step 7: Trim
Trim about 1 centimeter (1/2 inch) off of the top tube.
Step 8: How to use
Blow into the bottom tube. If you made it right, you should feel your breath going up your nose. Sniff as soon as you stop blowing. YOU CAN SMELL YOUR OWN BREATH!!!