Single engine failure in a light twin after lift-off: what to do? In a previous question the case about if a turnback would be feasible, specifically for a single engine aircraft, has been analysed.

But given a twin-engine general aviation aircraft and a single engine failure immediately after lift-off, considering that my Pilot handbook says:


  A continued take-off is not recommended if the steady rate of climb according to "Section XX" is less than Y%.


Considering the quite dangerous setting, I would say that is quite impractical to go and check that table in such a situation.

What kind of indicators might I look for to check if it safe to continue? Should I learn by heart such table? (I am not sure this is practical either, is a quite complex table)

In case I am unsure what to do, apart from trying to climb for a while then turn around or immediately try land in front of me (granted that there is enough space), are there, generally speaking, other options?

In the accepted answer of the listed question is said that


  It's not reasonable to try it [a turnaround] without knowing what altitude is needed for it at current conditions.


is it possible to estimate this quickly inside the cockpit?
What you really should learn by heart is the flight speed for best climb with one engine inoperative. Try to trim that immediately and you will win more time to make a decision. The rest is really depending on circumstances: Is there a landing opportunity ahead? Are you high enough to do a 180 and land on the same runway in opposite direction? Or are you high enough (and the aircraft does not lose altitude) that you can fly a pattern and land normally?

Testing the aircraft at altitude with one engine throttled is highly recommended, but be aware that the remaining thrust / drag of the throttled engine might be different from that of the stopped engine.