Wrap the cord/string around the hook to fasten it.
When you have pulled the blind up, wrap the cord around the hook to fasten it
When you have pulled the blind up, wrap the cord around the hook to keep it in place.
「留め金」＝ hook/clasp （ブラインドの場合、hookが一番良い）
「ひもを留め金に結びつけて固定する」＝ Wrap the cord/string around the hook to fasten it. （ブラインドの場合、cordが一番良い）
「ブラインドなどをひもを引いて上に上げた後で、留め金にぐるぐると巻き付けて固定する」＝ When you have pulled the blind up, wrap the cord around the hook to fasten it / When you have pulled the blind up, wrap the cord around the hook to keep it in place.
イギリス 
