Keep your memo specific, concise and respectful. Whether you are addressing a potential client or fellow employees, your recipients deserve to be treated with common courtesy.
Know your target audience. Customer service memos can address a variety of readers. If you are a manager, you may wish to address current company personnel regarding customer service policy and procedures. If you are a customer service representative, you may be writing to potential or current clients. Each of these target audiences have different needs and expectations. Having your target audience's needs and expectations first and foremost in your mind as you begin drafting your customer service memo will ensure that you assume the correct tone when composing your email.
Assign your customer service memo a subject line that is specific and appropriate to the email that is to follow. Be as specific as possible. If you are using a template to compose the customer service memo, use a subject line that at least covers the topic you are addressing in a way that will alert your recipients as to the content you plan to address. If you are replying to a prior email, do not use the automatically generated "Re:" as a subject line.
Make your point obvious at the very beginning of the email. Even if you are using a template, be sure that your memo is addressing a concern that is easily distinguished in the first or second line. This will ensure that your readers know that your memo directly affects them and will make it more likely that they will continue reading. This is particularly important in email communication, as many recipients assume messages that do not directly concern them are "spam", that is, "junk mail".
Check your grammar, punctuation and spelling before you send your memo. This may seem obvious, but forgetting to check correspondence for grammatical errors is a very common mistake made by professionals in every field. Typos not only make your memo sloppy, they also make your correspondence seem unprofessional and discredit the message you are attempting to convey.
Be sure to thank your readers. Leave the reader with the impression that you appreciate the time that they have spent reading your memo and provide contact information they can utilize should they have any questions or concerns.