I intended to make a short video on how to set up the Digitakt and Digitone, but ended up playing around for 10 minutes after I ran out of tutorial material.
With this setup, the Digitakt will act as the master: this is where you set the tempo, change patterns and press play/stop. Tracks 9-12 will mute the DN’s synth tracks 1-4, respectively. Very handy if you want all the mute buttons close to each other 
TL;DW:
- Connect the Digitakt’s (DN) output L/R into the Digitone’s (DN) Input L/R
- Connect the DT’s midi out to the DN’s midi in
- Go to the DN’s master page with func+LFO
- Set L in and R in to 100 and LPAN and RPAN all the way to the left and right respectively
- Go to Midi config - sync and make the DT send clock and program change, and set the DN to receive clock and program change
- On the DT, go to midi config - port config and set the mute destination to int+ext
- On the DT, go do midi config - channels and disable tracks 1-8, then set A to 1, B to 2, C to 3 and D to 4.
I hope it was helpful, and thanks for watching!