Keep her indoors
Close windows and doors
Provide a quiet, dim room
Offer a warm blanket or soft bed
Give extra attention and gentle petting if she wants it
Use interactive play to distract her
Keep a consistent routine
Use a pheromone diffuser made for cats
Clean litter boxes regularly
Avoid letting intact male cats near her
Do not punish or scold her
Contact a veterinarian about spaying
Ask a vet about safe calming options if needed