The first thing to do with posting a hard-copy letter is to source an envelope. The easiest way is to head over to accessories shop and but a pack of them. However, around this new era, sometimes, you only need just 1-2 envelopes a year but the shop sells you a pack of them. That's a lot of them. Also, using those envelope, you need to do custom printout.
What if there is a way to print a customizable envelope out on an A4 paper and you can just Do-It-Yourself (DIY) with double-sided tape, making it looks superbly professional? This post will guide you through different kinds of envelopes.
I obtained and customized this template original from a Singapore artist and now from Template Lab.com. Some modifications I did was porting to Google Drawing for scalability, removal of "scissors", reduces the embedded text to a shorter length without removing its meaning, and color striping the ribbon for indicating the confidentiality level / styling. Here's how it looks like after the editing:
File > Make A Copy
.File > Share
.Done
That's all about DIY an envelope using computing system. All you need is a suitable printer, a scissor, and a double-sided tape.