Make An Illuminated Scrolling LED Dot Matrix Sign for Your Layout

To put a new program on the Micro:Bit you juts plug it in to your computer via USB, got to the MakeCode webpage, update the program (ie. change the text you want to display), and then transfer that to the Micro:Bit.

Then unplug and put it back in your layout.

I could even make the program for you saying whatever you want, send it to you as a small file and you transfer it on to the Micro:Bit, just like dropping a file onto a USB drive.