~Finish the game on Expert difficulty~

WARNING: BEFORE STARTING A NEW GAME, MAKE SURE THE DIFFICULTY IS SET TO EXPERT ON THE OPTIONS MENU. ONCE IT IS, YOU ARE FREE TO START A NEW GAME. IF YOU FORGET TO DO THIS, THEN ALL YOU NEED TO DO IS CHANGE IT AS SOON AS YOU GAIN CONTROL OF DELSIN.

Whatever you do, do not change the difficulty at all on your expert playthrough, doing so will void the trophy. Expert difficulty isn't hard at all, it is on par with the previous inFAMOUS games if you have played those ones. This trophy would have been harder if the main story was longer, but as the main story only takes 6hrs to complete, this should be no trouble. You do not need to clear any of the D.U.P districts, just complete the main story for this trophy. Here are some basic strategies and things to remember:

Keep your distance to enemies. If the enemies are very close to you, they will kill you very quickly.
It's best to stay on rooftops. Enemies cannot follow you there so quickly and you have good cover.
Run away or hide when you are wounded. On Expert difficulty your health takes longer to recover. Just go up to a rooftop and wait until your health has replenished.
Get all the blast shards you can find to upgrade your powers. It will come in handy.
Don't waste your time with side missions and D.U.P. mobile command units. You can change back the difficulty to easy after you are done with the story and do these things later.
Use L2 to zoom in and go for headshots. Headshots do a lot of extra damage. Use the neon power a lot, hitting weak spots usually results in a one hit kill.
When you are on the island, during Hank's mission, or any other place with smoke and a roof, you can use Orbital Drop to glitch you bacl full health. Simply press DOWN ON THE D-PAD with a full karmaic streak, the animation will fail and you will land again, with full health and the ability to use it again.
Save your R1 attacks for large groups of enemies, armored vehicles and special enemies.

Boss Fight Tips

Eugene: He is the first proper boss in the game, and he is fairly easy to beat. You want to use the R1 attack with the neon power to hurt him, this does the most damage to him. If you run out of projectiles, then simply absorb some more neon out of the crystals. A neon crystal will respawn every time the arena changes. Also, when you are shooting him, make sure to hide behind the wide concrete pillars. This way you can dodge all of his attacks with ease and pretty much nothing will hit you.

Augustine #1: This is a fairly easy fight. All you need to do is shoot the "concrete shield" around her until it breaks. Once it has, keep shooting her and she will fall to the floor. All you have to do then is go up to her and press SQUARE. Repeat until you can use Orbital Drop. Now the second phase of the fight, you use video power. Simply do the same as before, use R1 to break her shield and then R2 to shoot her once she can be shot. Then, press SQUARE on her when she is on the floor. You'll get the karmic ability and you can finish her off.

Augustine #2: The final fight in the game isn't really that bad. For the first section, it's basically the same as you did in the first fight you had with her (mentioned above). Once you have defeated her, you'll have to watch a cutscene and you'll be given concrete powers. Now, at first you won't be able to do anything. Just keep dodging her attacks until Eugene throws a core relay down for you to absorb. You will get about 4 of them, and each will come after a set amount of time in the fight has passed. Once you have all the powers, I advise you upgrade the concrete powers if you have any shards on you, but this isn't necessary. All I upgraded was the R2 attack, for extended shots and the 10% and 20% health resistances. The fight takes a while to do, but the basic pattern is to keep shooting her, then when she comes running towards you, boulder dash to the other side of the lobby. When she shoots projectiles at you, this can be tricky to avoid. What I did was to run back and forth with boulder dash as soon as she fired at me. I would never get hit this way.