To unlock the "LIBERATION" trophy in Detroit: Become Human, you must choose revolution over demonstration going into the final chapter "BATTLE FOR DETROIT" and succeed in Markus' mission. Here are the steps.
*** Spoiler - click to reveal ***In "NIGHT OF THE SOUL" you must choose an assault on the camp to liberate the androids over peaceful demonstration. Public opinion won't make much difference if you choose this route.
Connor can be deviant or remain compliant, but in the latter case you will have additional work to do to make sure Markus succeeds.
Kara's path through the last chapter makes no difference to this trophy, however you should be aware that Markus' decision to fight impacts the options available to you for getting Kara through immigration into Canada; you'll have to sacrifice someone as you won't be able to in the border guard over.
At the start of Markus' march, you just need to move forward until you are prompted to plant the flag.
If Connor is still an obedient machine or died during CROSSROADS as a deviant, you'll now need to make sure Connor does not get to shoot Markus. One of two people will show up to stop him, just make sure that Connor loses (whether he is talked down, or loses a fight).
Back as Markus, you need to launch the assault on the camp. At the first point of cover, you need to look up and hold to attack the first soldiers, passing the QTE to take them out. This makes the next point of cover low risk. Head to it. Look to your left and get the androids to provide covering fire before moving up to the next point on the right. Do the same again here (no need to save your companion unless you feel like it).
Succeed at the QTEs when you go over the barrier. Decide what to do with the scared android, it doesn't seem to matter. Move up to the low risk barrier and then get yet more covering fire to move up to the next. Work your way forward by taking out more guards on the barrier with QTEs. Ignore another downed companion if they are still with you and get covering fire to move you up towards the next barrier. At the barrier where you are lying flat on your back the situation changes slightly. Tell the right-hand androids to charge while the left-hand androids provide covering fire and execute the attack. Next up, when everyone is getting mowed down by a machine gun, you have three groups to control. Get the left-most group (behind you) to provide covering fire while North's group and the group ahead to your right charge. Execute the manoeuvre and you should be able to finish off this stage of the attack.
If Connor was still compliant and died a few moments earlier on the rooftop, he'll return one last time for a scrap. You can pick to control Connor or Markus at this point. Choose Markus and get through the QTEs or choose Connor and fail them. Finally, shoot the RPG to finish the mission.
If Connor turned deviant at any point already then you'll just have to fight off a few more soldiers and then shoot the RPG.
Play through whatever is left of Kara's story (if anything) and, if Connor is deviant, decide what to do about the hacking attempt during Connor's final speech. Let the credits roll and get to the final flowchart.
The trophy will unlock when you reach the flowchart after the credits.