in fact you can go one better, and im sure someone will agree, come back in morning when its all gone dark all over, then with the trowel at a 40 degree angle, pull it backwards, TOWARDS you, VERY carefully to avoid leaving gouges in it..
this little technique will remove any lines missed from the day before (tiredness, rushing, labourers work etc) and by god will it polish it up, nice tip but you wanna avoid havin to if at all possible....