United airlines booking process is very simple and easily can done by anyone. Here are the steps suggested by http://www.ysupportnumber.com/united-airlines-customer-service :-

1- User should open United airlines official website https://www.united.com/
2- User should select departure and return date
3- Date of journey you should be selected
4- It is very important for you if you are going to book united airlines tickets then choose exact number of passengers
5- After selecting the number of passengers search flights
6- You will get flights details here

Process is very simple and effective if you want to book tickets. In the case of cancellation, reschedule flights or any other queries you should call to United airlines official department as they can suggest you best options and flights.