The First Arrow is in my opinion the most confusing part of the ridge walk - there's anumber of trails that split and merge, and the features used for navigation that are mentioned in Morphet guidebook all seem to look the same: like what they call 'red bluff' - to me they all look like red bluffs! Upon close analysis using Google Earth, everything seems obvious once you've seen the features, but if you dropped me off at the First Arrow today, I'd probably get lost again.
The main problem is that there are two options to get past the First Arrow: one through the drop-off which you need to climb, second - around the buttress and what they call an intermediate ridge. If you are hiking from the East, the option with the climb is difficult to follow because while descending into the drop-off it's hard to find the area where the climb is the easiest, so wandering around the top of the cliff with over 23kgs in the backpack wasn't my preferred option.
The second choice is technically much easier but requires better navigational skills. It's easy to descend to far down and end up on the trail leading to the fire road and further to boundary track, which is fine if you're planning to do only half ridge walk, but if your aim is to finish the whole ridge, you need to drag your arse back up and find your way through to the Castle Rock.
The place where the above panorama was taken, is in my opinion very important navigation feature that will (hopefully) help many ridge walkers to find their way through. This place on the photo above is what Morphet refers to as the narrow col. If you're walking towards Bluff Knoll, go down to the col but don't follow it down in either direction!!! - cross it and go around the rocks, then continue diagonally up and west traversing the northern buttress - you'll easily pick up the trail after few meters. Once the trail begins to descend again, that means you're on the intermediate ridge. From there, the trail will take you straight to the Castle Rock and further down to the camping area.