Loose Threads: Snip carefully with scissors. (Don't tug on them!)
Dirt: Lay flat and gently wipe or wash with a damp cloth. A mild detergent can be used.
Wrinkles or creases: A hot, wet towel moved over the crease will diminish it. Or, you can try a hand garment steamer from approximately 30 cm away.
Curled ends or edges: Roll in the opposite direction for 5 minutes
Frozen/Heated (from leaving in car in frigid or hot climate): bring to room temperature, roll out flat for 5 minutes
As often as possible, store Size & Space at room temperature.