When you shirr something, you gather fabric in parallel rows using elastic thread to create a decorative effect.
Shirring is often used in making clothes and decorations to make them look pretty and fancy.
Examples:
She shirrs the fabric to make a beautiful dress.
The curtains are shirred to give them a nice look.
I shirr the cloth to make a lovely pattern.
The shirred skirt looks so cute.
The shirred pillow adds a special touch to the room.
The shirred tablecloth makes the table look fancy.