Its wonky at first, took me a couple days total. Seems complicated at first but its not bad. You need 2 mod managers one for textures and one for everything else.
Start at thr nexus. Download everything before you start modding. METweak (something like that) will manage mods. The EGM (expanded galaxy map or something) has almost everything to make things way better (too much to list but amazing and he just updated it). Beyond that i added some of the mods reccomemded by that dude plus some others.
I modded out the little brat kid from the start. Modded the dreams to be super short. Modded out the ending so the brat never shows up and "we all win and now we go party at the citadel dlc".
For textures start with ALOT. It will redo all the textures, cutscenes and videos. Also has a suggested mod list and will deal with installing all of them. I downloaded every suggested mod and the god damn game looks amazing.
The way i suggest modding (works for all 3 games). Download everything first. You basically get one time compiling and modding then your stuck with it unless you repeat from the start. Imstall METweak exe and use it to make a back up the game (trust me). Then install ALOT. ALOT will have a list of suggeated mods download them. Now you are ready to mod the shit.
Open the METweak thingy and one by one drag and drop mods (NOT texture mods) into it, load them, then install them. Once all those are done open ALOT and drag and drop all the texture mods into it. Tell ALOT to install and it will smash everything into place (takes a minute). Then you are good to go.
I failed the first time and then figured it out. Ive had to restore from my back up twice but its easy now.
I know you like ME
@Zer and this makes ME3 pretty amazing imo. You can take old squad mates on missions if they are on your ship. You have tons of armor and weapons that you can use for squad members. You can have dlc trigger at better times in the story. It feels much better and looks amazing. I have a semi older rig and i have no problems with the 1080 textures. Best modding changes ive seen in a game in a long time.
Sorry for the long post but i was not expecting modding ME3 to be so bad ass.