Update README.md

Author: spinngit

README.md

@@ -5,7 +5,25 @@ This is a simple USB MIDI controller with 1 Pitch Fader, 1 Toggle Switch, 1LED a
 - MIDIUSB library is required.
 https://github.com/arduino-libraries/MIDIUSB
 
-<h3>Images</h3>
+<h2>Use case</h2>
+1. Connect this controller for your DAWs or PCDJ software. I use Native Instruments Traktor pro 3.
+
+2. Open and configure Controller Settings on Traktor PRO
+
+3. Choose the "Controller Manager" and select "General Midi" 
+
+4. Set notes from Togggle to Modifier Condition of M8 as C3= 1 / D3= 2.
+
+![image](https://user-images.githubusercontent.com/90672633/133881957-397f99d8-7c55-47b2-81b1-0a62c07269e4.png)
+
+4. Set Control Change value to Tempo Adjust (=pitch fader) with Modifier. if M8=1, Assignment="DeckA" and if MB=2, Assignment="Deck B".
+
+![image](https://user-images.githubusercontent.com/90672633/133881995-55ecfdb2-9e8d-4911-8a8c-e6558d207940.png)
+
+5. So you can pitch up/ pitch down with SL-1200 fader, and select Target Deck A/B by the toggle switch.
+
+
+<h2>Images</h2>
 
 ![_DSC0159_note1240 1](https://user-images.githubusercontent.com/90672633/133880499-0fc70cef-eaa9-44c8-b0c2-195c6d79a879.png)
 The Circuit