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By RipVW
Hi - Some of helpful tips I wish I knew when I started:

Because this has a built in USB:
* having the serial monitor open from a previous sketch interferes with uploading a new sketch.
* Serial.print done before the serial monitor is opened will not be seen once it is opened. To have the sketch wait for you to open the serial monitor, add add the following right after the Serial.begin statement

while (!Serial); // Wait for user to open Serial Monitor

Many arduino example sketches use the built in led connected to pin 13. On the pro micro this is at pin 17