Force cultivation is unique among the Ascension methodologies in that it does not rely on absorption of energy to cultivate. The main focus of a Force cultivator is their Will. Actual Ascension for a Force cultivator is simplicity itself, but the Path of Ascension in the Force is only for the truly devoted.
The Path of Ascension for the Force requires meditation, to be in tune with not just oneself, but with the world. While mana forcefully attunes its cultivator to be Aligned with its Concept, the Force is the sum of everything, what binds us and penetrates everything. It is the Will that Defines the world from the void. The meditator merely focuses on understanding this and feeling that connection and resonating with it.
Those with a greater ability to feel the connection are usually labeled Force sensitives. They can resonate with the world around them with an innate understanding that does not reach the conscious level. It is however, possible for even an ordinary person to feel the connection and resonate as long as the world's Laws do not restrict this privilege.
That being said, properly trained Force adepts on the Path of Ascension can be the most challenging of all the Ascenders to defeat in battle. Not only can they strengthen their bodies through their connection to the Force, they can perceive everything to the point of predicting the future, as well as manipulate the very world itself against their foes. The extent of their powers depends on training. The Jedi, who take an extremely passive approach to cultivating, excel at detection, future prediction, and body improvement, but are rather weak in terms of world manipulation. It takes rare talent to perform battlefield manipulation and manipulating others' minds is viewed as skirting close to the dark side. On the other end of the spectrum, the Sith are too forceful with their approach to the Force, focusing on their own desires and how to affect the world rather than how they are affected by it. They tend to excel at world manipulation, but their detection skills are weak, and future prediction skills are usually non existent.
Force affinities are usually implemented based on whatever Force sensitivity a cultivator has inherited, though one can learn all the powers of a Force user if one is willing to put in the effort just like an normal person. One can also boost their sensitivity with energy absorption to practice powers they have no affinity for.
There are several thresholds to criss in Force cultivation, but they all are a matter of skill and sensitivity rather than power. One who is sufficiently talented in both can Ascend rather quickly. First, one must learn to sense the Force. Second, one must learn how to resonate with it. Third is learning how to manipulate the world. Fourth is to become the world when one Ascends.
I want to mention that both Jedi and Sith share the commonality of constructing a lightsaber as part of their cultivation. They do this to learn how to resonate with that which is alien to them. While there are a rare few who resonate with the machine, most require the step of creating a machine that only works because all its parts fit and resonate together perfectly. This insight not only helps them understand how everything is connected, but lightsabers are also preferred by both sects for personal combat. When a fighter is up close and personal, no only is it easier to manipulate the world around him, but he is able to perceive how everything reacts to the changes in resonance when a very Force attuned weapon cuts down an enemy.