The mechanism for the hydrolysis of an imine is several steps. When asked to recall a mechanism like this, sometimes a sense of dread comes over a student.  It seems like too much to memorize. But, notice that the first step is that the nitrogen atom of the imine is protonated. I think it’s best to remember than in acidic conditions, this is the first step of the mechanism. When asked to recall this mechanism, I do not panic. I simply remind myself of a simple phrase, “Protonate, and go to town.” This calms me down and I just write down the first, protonation step of the mechanism and let the water attack. After that, I “go to town”. That means, I figure out the remaining parts of the mechanism as I go along. I keep protonating the nitrogen until it comes off and deprotonate the water until all of the protons are removed from the oxygen atom. Also, notice that never, in any of the mechanism’s steps, is there ever a situation where there are two positive charges. There is one positive charge, it becomes neutral, then positive again, then neutral, but never doubly positive.