Uploading for the first time docs from @fjansson (#699)

Fixes #688

Author: earlephilhower

docs/install.rst

@@ -65,6 +65,26 @@ Them hit the upload button and your sketch should upload and run.
 In some cases the Pico will encounter a hard hang and its USB port will not respond to the auto-reset request.  Should this happen, just
 follow the initial procedure of holding the BOOTSEL button down while plugging in the Pico to enter the ROM bootloader.
 
+Unable to Upload First Sketch
+-----------------------------
+If the Arduino IDE has never seen a serial port from a working device (Pico, AVR, or any other serial port), you
+may not be able to install using the prior directions because the ``Tools->Port`` menu will be grayed out and
+empty.  In this case, a special workaround identified by @fjansson in `this issue report <https://github.com/earlephilhower/arduino-pico/issues/688>`_ .
+
+To allow subsequent uploads to automatically work, you will need to manually install a UF2 binary onto the Raspberry Pi Pico one time to
+allow it to present a Serial port for the Arduino IDE to detect and save. 
+
+Perform the following steps to program a dummy sketch:
+
+1. Open a new, empty sketch (doesn't work with a read-only example sketch).
+2. Compile it by pressing the "Verify" checkmark button.
+3. Select the ``Sketch -> Export Compiled Binary`` menu. Select a location e.g. the desktop. A folder is created there, containing a file ending in .uf2
+4. Copy this file to the Pico's drive, by drag and drop in the Explorer.
+
+The Pico restarts and now now has a serial port. Now the Port menu in Arduino is not gray anymore, select the port there.
+After this, normal uploading from the Arduino editor should work.
+
+
 Windows 7 Driver Notes
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