Good luck - plugs out has to be the biggest tip.
When you remove the injectors you may well find the system is still pressurized a little and fuel will bubble over from the rail into the bores and will continue to do so for a bit filling up the bores.
Turn engine over with plugs removed and/or crank sensor disconnected to force this petrol out if its allot. Or if just a dribble it will evaporate by the time you have fitted the new ones.
If you can leave the car standing overnight and not prime the pump at any point and then do the job, it might/should avoid this problem.
If the injectors don't feel like its seated down correctly it probably hasn't. Oh and you might end up crimping an 'O' ring if your unluckly so you might want a spare 'o' ring or 2 to hand just in case.
And probably not a bad idea to have a fire extinguisher to hand just in case
