Responding to customers in writing daily could lead to a form of “writer’s block” where although you may know the correct answer, you still stumble over getting that information out.
One thing to consider for these situations is “canned responses” — not form letters, but more basic templates to get the ball rolling and the creative juices flowing. Communicating with customers is all about getting the information across in a form best understood by the person receiving it. A “saved reply” provides the basics; you can fill in the “blanks.”
Always use an appropriate salutation and personalize the response to the subject and the recipient.
Also, keep in mind that if the customized “template” you are going to send feels a bit “canned,” it will mostly come across as such. In some cases, this may be fine, although, for the most part, it will always be a good thing to read, edit, re-read, and edit your response some more before sending it out — make those little tweaks so your response will be more personalized and on point.
Remember, writing begets writing; consider some off-topic personal writings to shake things up and give yourself some ideas and methods to improve your written communication skills. Maybe start a blog about support?