Slightly longer short answer
Standard string lights cannot be shortened safely and effectively.
Hey, I think you are saying "No" but can't the wires be cut and re-soldered?
So, yes you could cut and solder your lights, BUT, a string of incandescent lights contains bulbs that are rated for a specific length and number of bulbs. Change the number of bulbs or change the resistance of the light string and the lights won't last as long as they should - or they might not come on at all. The lights will burn out faster - usually one at a time -
If your light string is LED, they are ultra-low current and ANY kind of modification will either ruin them or significantly lower their lifespan. Don't take this risk with your investment.
What's the solution?
- Choose a shorter light string.
- Choose two much shorter strings.
- Wind up the leftover lights and tuck them under an eave or physically hide them within your project.
- Visually disguise extra bulbs with a little piece of electrical tape if there aren't too many.
Hope this helps and saves you time and trouble as you light your home of business for Christmas or for a party this Friday.