With the Classless Progression, each character is not a specific class. They do not gain class abilities based on their class chosen, and instead receive full freedom and flexibility to build their character as they want - at the risk of an incredibly unbalanced game. This can create unique combinations, but at the same time, result in very unexpected and broken builds. Use these rules with care.
Each character gains levels as normal, however there is no level cap. Level starts at 1, and can go as far as the character wants. Levels past 20 only gain new Feats and Class Abilities however.
Characters gain HP, Soak, and Attacks per Round as per a Rogue, and Skill Ranks as per a Forger.
Characters gain proficiency with Simple and up to four weapons types. They can sacrifice one weapon proficiency to gain Armor Proficiency. They can also sacrifice two to gain an Exotic Weapon Proficiency.
Every level, characters choose a class ability from a class that is gained at the level you're at or lower. This includes archetypes, and Advanced Classes (Advanced Classes add their Level Prerequisite to the level requirement. Example, a Level Prerequisite of 5th means a 1st level Advanced Class ability could only be taken at 6th level).
Class abilities which grant the same bonus do not stack unless otherwise stated. Spellcasting can only be gained once, and once gained the character can cast spells as per a Mage of equal level (gaining MP based on their progression).
Levels in which an Awakening would be gained, the character can choose an Awakening to gain. This Awakening can be from a weaker Awakening, but not from a greater one. Example, you can use your Unchained Awakening to gain access to a class' Heroic Awakening, but not their True Awakening.