Nice system - though the record player is not the correct model and does not usually work with this system - it uses an older language for linking and also does not have a built in RIAA, which it needs. I have a suspicion that you will get very low volume when you try to use it.
In the first event I would see if everythingt works. The CD player and Beocord will plug into the Beomaster via the captive 7 pin DIN plugs - the sockets are marked. Once plugged in, attach the speakers - if you have the twin grille S45, then these too have captive leads with 2 pin plugs which will plug directly into the Beomaster. You should also have two aerials - one will be a simple piece of wire - the AM aerial - with a two pin plug on the end and probably a T aerail with a co-axial plug. Attach these.
Did you get a remote? You will need one if you didn't! Attach to the mains and see if everything works. I'll see if I can find the mounting instructions!