My Mom always says "If you love it, Handwash it"
Then there's real life.. where I toss everything I own in the washer and check it off my 'TO DO' list.
You can wash your Necknot in a delicate garment bag on handwash/delicate/low manipulation cycle on a front loading washing machine. Use the Cold Water Setting.
Don't put it in the Dryer! Simply lay flat on a towel to dry, or hang by the knot on a hanger.