Update assembleyourcard10.md: add some notes at the top, link to next step

en/assembleyourcard10.md

 # Assemble your card10
 
+The main components of your card10 are two electronic boards, the _fundamental_ board and the _harmonic_ board. 
+The _fundamental_ board sits directly on the wrist band, the _harmonic_ board with the display sits on top of it.
+If you are curious to learn more about the two boards, you can find a more detailed description on the [hardware overview](/en/hardware-overview/) page.
+When unpacking and assembling, make sure to keep your protective foil on the display at first, until you had a look at the 
+[polarizing display](/en/faq/#why-should-i-consider-keeping-the-protective-foil-on-the-display) faq section.
+
 <img class="center" alt="harmonic board with glue dot" src="/media/assemble/IMG_20190819_143216.jpg"  width="420" height="auto" align="center">
 
 - use the glue dot to attach the battery to the harmonic board
@@ -27,5 +33,6 @@
 
 
 ## Have fun with your card10!
+Now it's time to (switch on)[/en/gettingstarted/#switching-your-card10-on-and-off] your card10.
 
 <img class="center" alt="happy hacking" src="/media/assemble/IMG_m6w9xw.jpg"  width="420" height="auto" align="center"> 
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