Become An Expert in Running and Returning

When a person wants to travel in the paths of Teshuva, he needs two expertise. He must be an expert in 'running' and 'returning', meaning in the elements of advancing and receding, which are the concepts mentioned in the verse "If I ascend up into heaven, You are there; if I make my bed in hell, behold, You are there." Meaning, it is not possible for a person to do Teshuva unless he is firm and strong in his mind, that he will constantly serve Hashem regardless if he is holding on a high level, relative to his stature where he is in a state 'advancing', in line with the concept of 'If I ascend up into heaven, You are there' or whether he falls from his level and is now holding on an extremely low small level, in the pits of hell, Heaven forbid. Despite this he must not let himself despair and instead should strengthen himself and grasp on to whatever service of Hashem he can at that point, in line with the concept of 'if I make my bed in hell, behold, You are there'. Even in in the lower realms of Hell, Heaven forbid, even there Hashem exists and is willing to hold a person's hand, allowing him to come close to Him, even from there. When a person has these two expertise, then he goes in the paths of Teshuva and merits the Glory of Hashem and then Hashem's right hands is stretched to accept his repentance.

(Kitzur Likutay Moharan Hayashon Torah 6 Clause 6)

Learn Torah Although You Forget It

There is a parable about a person that studies torah and forgets it: A group of men were once hired to fill up barrels. However the barrels had holes in them and as much as the workers would pour in would end up spilling out. The foolish workers said "since everything ends up leaking out of the barrels, why should we work so hard to fill them, since afterwords it all spills out?" The wise worker on the other hand said, "What do I care, they are paying me by the day, and regardless they will not hold back my salary since I am already hired fro a certain amount of time, what difference does it make to me if it spills out of the barrels?" So too a person that forget what he learns, his compensation will also not be held back for each day he studied.

Also know, that in the future world they remind each person everything he studied, although he forgot it. Even people that hear the Torah of the True Tzadik and do not understand it, in the Next World they will understand it. This is because the main reason of Torah study is for the soul, so in the Next World the souls will be experts and grasp well the Torah that a person studied and heard in This World. Fortunate is a person who passes all his days immersed in much Torah study and service of Hashem.
(Sichos Haran 26)