Fax machines are often shared by offices or several people within an office. Since anyone can see a fax sent to a fax machine, it is a good idea to include a cover letter. This will ensure that your fax gets to the correct person. The cover letter includes information like the recipient’s name, the content of the fax, and how many pages it includes. It should also include the sender’s information, such as name and fax number, so that the recipient will know whom it came from and can reply if necessary. Next, you will need to dial the fax number, just the same way you would on a telephone. On most new fax machines, the area code will not need to be dialed for a local number but is still necessary for long distance numbers. Some fax machines require the area code regardless of location. Check or ask about your machine.  The country code (the number 1 for US phones and fax numbers) will also sometimes need to be dialed before local numbers but only when the area code is also required. The country code is almost always necessary to dial long distance numbers. You will often also need to dial 9 before dialing long distance numbers. Check the specifications for or ask about your individual fax machine. Be sure that the number you are using is the fax number and not the phone number of the person you are trying to reach. Often the numbers will be listed next to each other on business cards and it is easy to misread it or look at the wrong number. When you put the materials to be faxed into the machine, you will need to put them in in the appropriate direction. The paper will be scanned, so if the paper is facing the wrong way only the back side will be scanned and the fax you send will be blank. Ensure that the papers a facing the right side up before sending the fax. Different fax machines feed in different ways. Helpfully, all fax machines are labeled with the appropriate direction to place the papers. Somewhere near the area where you feed the paper, look for a symbol of a sheet of paper with a corner folded...

TL;DR in Chinese:
写封附件。 拨传真号码。 确定操作方法。 传对文件。