Another thing I thought of.
CUT the tape to length with the plastic anti-stick still on it first.
Peel off a little of the plastic and get it to stick about 2" in from the end to get the piece started (you'll come back later and get that end stuck later)
Peel the plastic off as you lay it down, just a little at a time and use your fingers to stick the tape and keep it straight- just in spots at first.
As you finish getting the whole thing in place and "tacked" with your fingers, you can go back now and get every bit of it stuck down well.
Be sure to push the tape INTO lips and edges. If it bridges a gap, it can fail. It should push into the gap, climb up the lip, then go over the top of the lip, NOT make a slope over the gap. Make sense?
Another way to say that is say you have two different thickness layers meeting. The tape should be completely flat against the bottom layer, pushed into the 90 degree corner, pushed flat against the vertical edge to the top of the upper part of the joint, then lay over 90 degrees on the top layer. Like a "Z" shape.
Given a choice, it is better to use multiple pieces and get them into place properly than to have one continuous piece that is hard to handle and get pushed into all the nooks and crannies.
If you get a spot you don't like that gets thin, doesn't go into all the voids, whatever, simply get it all pressed into place and go over it with another piece. It's designed to layer when needed.
Much of this info is what I recall from the Eternabond instructions when we did it.
Be patient! Do it correctly and you will be quite pleased with the results :)