Hello Lee,
Look at the door seal on the ouside of the machine you may have a large circular spring with a tightening screw which you must undo and then take the rubber seal off, you will then need to take the rest of the door seal off the main drum, see if there is a circular spring on there as well, sometimes they do sometimes not.
The new door seal must be fitted the correct way up, you will see a mark on the door seal, put some washing up liguid round the edge of the rubber seal and fit it over the drum, screw spring back, pull the rest of the rubber seal through the door and put some washing up liquid round the edge and ease it over the front of the machine, screw the spring back on, make sure the drain holes are at the bottom, take your time, it is fidley.
Ken
Make sure the plug is out when you work on the machine.
drivewithken@blueyonder.co.uk, July 2007