Dear scarlett24
first of all , wish you the best of luck ..
Open day [ CV Drop only ]
assessment day usually the day after OD.
BUT in some cases IF only around 50s people show up to attend the OD . the recruiters can skip the open day stage and go direct for assessment .
but i don't think that gonna happen in Alexandria , because there will be A LOT
of candidates .
all you need to bring to OD is your CV, Passport size & Full length photographs . you don't need anything else for this stage . of course you will be wearing a business attire . it will be only a short chit chat , like whats your name , how old are you and where do you work . and if you'll be successful you'll receive a message ( SMS ) or a phone call advising you to attend the assessment day which will be the next day .
wish you the best of luck ..