Is there anything unique for a Guido tether?
Just a few basic knots you should know anyway. From the top end down: Stopper knot (I hang my bow on it), Figure 8 on a bight large enough to pass a carabiner and Ropeman through. Tag end: Stopper knot OR a smaller Figure 8 on a bight to double clip onto your carabiner as a backup.
Yale bandit rope holds knots really well and works GREAT with Ropeman 1, and Blake's hitches or prusik.
You can buy pre made prusik loops. Much tidier than tying your own.
I highly recommend the Ropeman 1. You can also back it up with a prusik. You'll feel safer if you do. I recommend a pear shaped carabiner. Easy to work with gloves. Petzl William is nice.