Here's what you *can* try, but none are guaranteed to work and some could cause damage:
* Interior Release: If you can get into the car, the obvious solution is to use the interior trunk release lever or button.
* Fishing Through Gaps: Try to carefully fish around any gaps in the trunk or around the rear lights with a coat hanger or similar tool to see if you can reach the latch mechanism. This is difficult and risky; you could easily scratch or break something.
* Spare Key: Check with family members, roommates, or other people who might have a spare key.
* Professional Locksmith: This is the safest and most reliable option. A locksmith has the tools and expertise to open the trunk without damaging your car. They might even be able to make you a new key.
Avoid attempting any forceful methods as you risk causing damage to the car's body, paint, or the locking mechanism itself. Calling a locksmith is always the best option if you're locked out and can't access the interior.