PLS help me to fix this sentences, english beginner~?

wow this is really bad ya know,This Afternoon,with two of my sales department colleagues,i went to visit a customer in Shanghai.For many reasons we had arrived late.It was 3pm and we still hadn't had our lunch, so first we ate and then we went to visit our customer.Because my two sales department colleagues had to go to Qingdao the next day,we all had to be back in Shanghai by 6pm,where our superintendent along with other sales colleagues were waiting for us at a restaurant. They had seen my colleagues and i off and at last we went to KTV and then went home at midnight. It was very late and i was so tired that i could do nothing else that night but go to sleep.