How do I make my BIC stay lit?

There are a few things you can try to make your BIC lighter stay lit:
Adjust the flame: Use the flame adjuster at the bottom of the lighter to increase or decrease the size of the flame. If the flame is too small, it may not stay lit.
Check the fuel level: Make sure your lighter is not running low on fuel. If it is, refill it with butane.
Purge the lighter: Hold the lighter upside down and press the refill valve with a small tool like a screwdriver. You should hear a hissing sound, which indicates that the lighter is purging the air. This can help to ensure that there is no air trapped in the fuel chamber, which can cause the lighter to go out.
Try a different grip: Some people find that gripping the lighter too tightly can prevent it from staying lit. Try holding it more loosely.
If none of these methods work, the lighter may be defective and you may need to replace it.

How many BIC lighter designs are there?

BIC, the company that produces BIC lighters, has a wide range of lighter designs that come in different colors and sizes. However, it's difficult to provide an exact number of designs as new designs are released regularly and some may be discontinued over time. Additionally, BIC lighters may also have limited edition designs that are only available for a certain period.