I would recommend you focus on learning mechanisms generally - in other words, write all parts of the molecule that do not react directly in the mechanism as "R1", "R2", "R3", etc. This will help you keep it general - you will be able to apply the reaction and understanding you have learnt to any molecule. The purpose of learning mechanisms rather than reactions themselves is so that you can apply the mechanism to any case. For example, it is far better in my opinion to learn the addition of E-Nu to a C=C double bond (where Nu is the more electronegative segment and E is the less electronegative segment) than to learn what happens when this is HCl - because then you'd realize that HCl could indeed be a long organic chain that ends in Cl and in principle the same thing happens! (The C-Cl bond breaks and you get a + charge on the C, bonding to the less substituted carbon, and a - charge on the Cl which bonds to the more substituted C. This comes from learning the mechanism and Markovnikov's Rule which accompanies it). So basically, make sure you learn general cases of the mechanisms rather than rote-learning what happens when propene reacts with HCl.