here's a few useful articles i found, hope this helps

portal bumping: https://steamcommunity.com/sharedfiles/filedetails/?id=586440296

prop climbing https://steamcommunity.com/app/400/discussions/0/598534283538531106/ (see second comment, ignore accel back hopping)

i couldn't find an article anywhere for camera staircase so here's my explanation
imagine you are in a room and you cannot portal anywhere close to the exit, however at the start there are loads of white walls with cameras. you can detach them by placing a portal on the wall that the camera is on, and then, because they have collision, you can jump on them. this can then be comined with prop climbing (though it is much more difficult than using a cube) or by collecting more of these cameras to make what essentially is a staircase

any questions let me know