How to properly use Galecaller's? Exsanguinate?

[Fyfaesia 0]

As the title states, what is the proper way to use this trinket if one is running Exsanguinate/Subterfuge and two stacks of Shrouded? Should I be trying to always line it up with Exsanguinate or simply using it as it comes off CD and am able to stand still long enough to benefit from the buff? 

Beyond this, I am new to playing with Exsanguinate and was also wondering if you should save Exsanguinate for Vendetta/Vanish combos? How long is it OK to hold on to Exsang once it comes off CD? 

Thank you

[Carrn 281]

You can get every second Exsang with it if you use them both on cooldown (use Galecaller's prior to Exsang), but I found it to be much easier to use it with Vendetta since you'll have an Exsang for every Vendetta anyways (even if you use it a bit later in the Vend window)

7 hours ago, Fyfaesia said:

How long is it OK to hold on to Exsang once it comes off CD? 

I was holding off on the second Vendetta casts most of the time (by ~10s), to make sure it lined up with the 3rd Exsang, prepare all the bleeds, and make sure it would happen at a point where I wouldn't need to swap targets or move