Great thread and helped me loads to remove bumper on e91 2006 to replace my headlights (cracked lenses) which overall took about 5 hrs to do the lot but could probably do in 3 no problem now
Anyway, hope my observations on a couple of areas helps someone else - most is amply covered in previous details and photo's but a couple of areas weren't quite clear to me before starting..
Firstly - recommend jacking up, removing wheels AND front wheel arch liners - I didn't because of the blinkin lack of jack in a BMW due to those pesky runflats!!! (seriously BMW - they are rubbish and have put me off another!!)
Rant over, remove wheel arch liners if possible, or at least enough to free up space for the top bumper securing bolts attaching it ti the wing anyway - I had difficulty because of the limited space with wheel present - but turning the wheel outwards is best and then just a case of pulling out the liner as best as possible. Photo below shows the bumper off and you can see 1 of the 2 bolt holes at the top flange which bolt onto a mating inside return flange on the wing.
Washer jet covers - no springs or anything on mine (see photo) and I bust one but saved the other - they locate by locating 2 slots onto two short spigots on each side of the jet just about visible (dark black in photo) and dont even try just flexing the bumper away from the car before removing these which is what I did and 'PING' I was one down.
whoever said operate the washer and grab the nozzle before it goes back inside was genius!!! - but return spring is very strong so is a bit awkward too do single handed - needs 3 of you - one to operate the washer, one to grab the jet and one to carefully prise and wiggle off the cover.
BTW they are £14.88 from BMW, plus a can of paint and lacquer from halfords £13 and job done (BMW wanted £24 just for the paint aerosol, no lacquer).
Incidentally, top bolt at top rear corner of headlight assembly is a pig - takes a T30 torx and no room to maneouvre but at least once cracked 1/2 a turn just spins off.
Hope the photo's help