[exim] forward

Hello,

Please somebody could guide me from the begining? I need to deliver the
email that arrives to the recipient aaa@??? to another address
bbb@???
I know i have to create a .forward somewhere, i have installed OpenLdap so i
guess home directories do not apply

also i know that i have to issue the command
#exim4 -bf /path/.forward
or -bF for to be real

i have tried it but nothing happens... as soon as put the command, it stays
forever, without giving to me the shell again..

how can i make this test?

thanks